Examples（示例）
Get started（入门）
A very simple hello world label
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_LABEL
/**
* Basic example to create a "Hello world" label
*/
void lv_example_get_started_1(void)
{
/*Change the active screen's background color*/
lv_obj_set_style_bg_color(lv_screen_active(), lv_color_hex(0x003a57), LV_PART_MAIN);
/*Create a white label, set its text and align it to the center*/
lv_obj_t * label = lv_label_create(lv_screen_active());
lv_label_set_text(label, "Hello world");
lv_obj_set_style_text_color(lv_screen_active(), lv_color_hex(0xffffff), LV_PART_MAIN);
lv_obj_align(label, LV_ALIGN_CENTER, 0, 0);
}
#endif
Create a slider and write its value on a label
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_SLIDER
static lv_obj_t * label;
static void slider_event_cb(lv_event_t * e)
{
lv_obj_t * slider = lv_event_get_target(e);
/*Refresh the text*/
lv_label_set_text_fmt(label, "%"LV_PRId32, lv_slider_get_value(slider));
lv_obj_align_to(label, slider, LV_ALIGN_OUT_TOP_MID, 0, -15); /*Align top of the slider*/
}
/**
* Create a slider and write its value on a label.
*/
void lv_example_get_started_4(void)
{
/*Create a slider in the center of the display*/
lv_obj_t * slider = lv_slider_create(lv_screen_active());
lv_obj_set_width(slider, 200); /*Set the width*/
lv_obj_center(slider); /*Align to the center of the parent (screen)*/
lv_obj_add_event_cb(slider, slider_event_cb, LV_EVENT_VALUE_CHANGED, NULL); /*Assign an event function*/
/*Create a label above the slider*/
label = lv_label_create(lv_screen_active());
lv_label_set_text(label, "0");
lv_obj_align_to(label, slider, LV_ALIGN_OUT_TOP_MID, 0, -15); /*Align top of the slider*/
}
#endif
Styles（样式）
Size styles
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_IMAGE
/**
* Using the Size, Position and Padding style properties
*/
void lv_example_style_1(void)
{
static lv_style_t style;
lv_style_init(&style);
lv_style_set_radius(&style, 5);
/*Make a gradient*/
lv_style_set_width(&style, 150);
lv_style_set_height(&style, LV_SIZE_CONTENT);
lv_style_set_pad_ver(&style, 20);
lv_style_set_pad_left(&style, 5);
lv_style_set_x(&style, lv_pct(50));
lv_style_set_y(&style, 80);
/*Create an object with the new style*/
lv_obj_t * obj = lv_obj_create(lv_screen_active());
lv_obj_add_style(obj, &style, 0);
lv_obj_t * label = lv_label_create(obj);
lv_label_set_text(label, "Hello");
}
#endif
Background styles
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES
/**
* Using the background style properties
*/
void lv_example_style_2(void)
{
static lv_style_t style;
lv_style_init(&style);
lv_style_set_radius(&style, 5);
/*Make a gradient*/
lv_style_set_bg_opa(&style, LV_OPA_COVER);
static lv_grad_dsc_t grad;
grad.dir = LV_GRAD_DIR_VER;
grad.stops_count = 2;
grad.stops[0].color = lv_palette_lighten(LV_PALETTE_GREY, 1);
grad.stops[0].opa = LV_OPA_COVER;
grad.stops[1].color = lv_palette_main(LV_PALETTE_BLUE);
grad.stops[1].opa = LV_OPA_COVER;
/*Shift the gradient to the bottom*/
grad.stops[0].frac = 128;
grad.stops[1].frac = 192;
lv_style_set_bg_grad(&style, &grad);
/*Create an object with the new style*/
lv_obj_t * obj = lv_obj_create(lv_screen_active());
lv_obj_add_style(obj, &style, 0);
lv_obj_center(obj);
}
#endif
Border styles
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES
/**
* Using the border style properties
*/
void lv_example_style_3(void)
{
static lv_style_t style;
lv_style_init(&style);
/*Set a background color and a radius*/
lv_style_set_radius(&style, 10);
lv_style_set_bg_opa(&style, LV_OPA_COVER);
lv_style_set_bg_color(&style, lv_palette_lighten(LV_PALETTE_GREY, 1));
/*Add border to the bottom+right*/
lv_style_set_border_color(&style, lv_palette_main(LV_PALETTE_BLUE));
lv_style_set_border_width(&style, 5);
lv_style_set_border_opa(&style, LV_OPA_50);
lv_style_set_border_side(&style, LV_BORDER_SIDE_BOTTOM | LV_BORDER_SIDE_RIGHT);
/*Create an object with the new style*/
lv_obj_t * obj = lv_obj_create(lv_screen_active());
lv_obj_add_style(obj, &style, 0);
lv_obj_center(obj);
}
#endif
Outline styles
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES
/**
* Using the outline style properties
*/
void lv_example_style_4(void)
{
static lv_style_t style;
lv_style_init(&style);
/*Set a background color and a radius*/
lv_style_set_radius(&style, 5);
lv_style_set_bg_opa(&style, LV_OPA_COVER);
lv_style_set_bg_color(&style, lv_palette_lighten(LV_PALETTE_GREY, 1));
/*Add outline*/
lv_style_set_outline_width(&style, 2);
lv_style_set_outline_color(&style, lv_palette_main(LV_PALETTE_BLUE));
lv_style_set_outline_pad(&style, 8);
/*Create an object with the new style*/
lv_obj_t * obj = lv_obj_create(lv_screen_active());
lv_obj_add_style(obj, &style, 0);
lv_obj_center(obj);
}
#endif
Shadow styles
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES
/**
* Using the Shadow style properties
*/
void lv_example_style_5(void)
{
static lv_style_t style;
lv_style_init(&style);
/*Set a background color and a radius*/
lv_style_set_radius(&style, 5);
lv_style_set_bg_opa(&style, LV_OPA_COVER);
lv_style_set_bg_color(&style, lv_palette_lighten(LV_PALETTE_GREY, 1));
/*Add a shadow*/
lv_style_set_shadow_width(&style, 55);
lv_style_set_shadow_color(&style, lv_palette_main(LV_PALETTE_BLUE));
/*Create an object with the new style*/
lv_obj_t * obj = lv_obj_create(lv_screen_active());
lv_obj_add_style(obj, &style, 0);
lv_obj_center(obj);
}
#endif
Image styles
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_IMAGE
/**
* Using the Image style properties
*/
void lv_example_style_6(void)
{
static lv_style_t style;
lv_style_init(&style);
/*Set a background color and a radius*/
lv_style_set_radius(&style, 5);
lv_style_set_bg_opa(&style, LV_OPA_COVER);
lv_style_set_bg_color(&style, lv_palette_lighten(LV_PALETTE_GREY, 3));
lv_style_set_border_width(&style, 2);
lv_style_set_border_color(&style, lv_palette_main(LV_PALETTE_BLUE));
lv_style_set_image_recolor(&style, lv_palette_main(LV_PALETTE_BLUE));
lv_style_set_image_recolor_opa(&style, LV_OPA_50);
lv_style_set_transform_rotation(&style, 300);
/*Create an object with the new style*/
lv_obj_t * obj = lv_image_create(lv_screen_active());
lv_obj_add_style(obj, &style, 0);
LV_IMAGE_DECLARE(img_cogwheel_argb);
lv_image_set_src(obj, &img_cogwheel_argb);
lv_obj_center(obj);
}
#endif
Arc styles
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_ARC
/**
* Using the Arc style properties
*/
void lv_example_style_7(void)
{
static lv_style_t style;
lv_style_init(&style);
lv_style_set_arc_color(&style, lv_palette_main(LV_PALETTE_RED));
lv_style_set_arc_width(&style, 4);
/*Create an object with the new style*/
lv_obj_t * obj = lv_arc_create(lv_screen_active());
lv_obj_add_style(obj, &style, 0);
lv_obj_center(obj);
}
#endif
Text styles
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_LABEL
/**
* Using the text style properties
*/
void lv_example_style_8(void)
{
static lv_style_t style;
lv_style_init(&style);
lv_style_set_radius(&style, 5);
lv_style_set_bg_opa(&style, LV_OPA_COVER);
lv_style_set_bg_color(&style, lv_palette_lighten(LV_PALETTE_GREY, 2));
lv_style_set_border_width(&style, 2);
lv_style_set_border_color(&style, lv_palette_main(LV_PALETTE_BLUE));
lv_style_set_pad_all(&style, 10);
lv_style_set_text_color(&style, lv_palette_main(LV_PALETTE_BLUE));
lv_style_set_text_letter_space(&style, 5);
lv_style_set_text_line_space(&style, 20);
lv_style_set_text_decor(&style, LV_TEXT_DECOR_UNDERLINE);
/*Create an object with the new style*/
lv_obj_t * obj = lv_label_create(lv_screen_active());
lv_obj_add_style(obj, &style, 0);
lv_label_set_text(obj, "Text of\n"
"a label");
lv_obj_center(obj);
}
#endif
Line styles
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_LINE
/**
* Using the line style properties
*/
void lv_example_style_9(void)
{
static lv_style_t style;
lv_style_init(&style);
lv_style_set_line_color(&style, lv_palette_main(LV_PALETTE_GREY));
lv_style_set_line_width(&style, 6);
lv_style_set_line_rounded(&style, true);
/*Create an object with the new style*/
lv_obj_t * obj = lv_line_create(lv_screen_active());
lv_obj_add_style(obj, &style, 0);
static lv_point_precise_t p[] = {{10, 30}, {30, 50}, {100, 0}};
lv_line_set_points(obj, p, 3);
lv_obj_center(obj);
}
#endif
Transition
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_IMAGE
/**
* Creating a transition
*/
void lv_example_style_10(void)
{
static const lv_style_prop_t props[] = {LV_STYLE_BG_COLOR, LV_STYLE_BORDER_COLOR, LV_STYLE_BORDER_WIDTH, 0};
/* A default transition
* Make it fast (100ms) and start with some delay (200 ms)*/
static lv_style_transition_dsc_t trans_def;
lv_style_transition_dsc_init(&trans_def, props, lv_anim_path_linear, 100, 200, NULL);
/* A special transition when going to pressed state
* Make it slow (500 ms) but start without delay*/
static lv_style_transition_dsc_t trans_pr;
lv_style_transition_dsc_init(&trans_pr, props, lv_anim_path_linear, 500, 0, NULL);
static lv_style_t style_def;
lv_style_init(&style_def);
lv_style_set_transition(&style_def, &trans_def);
static lv_style_t style_pr;
lv_style_init(&style_pr);
lv_style_set_bg_color(&style_pr, lv_palette_main(LV_PALETTE_RED));
lv_style_set_border_width(&style_pr, 6);
lv_style_set_border_color(&style_pr, lv_palette_darken(LV_PALETTE_RED, 3));
lv_style_set_transition(&style_pr, &trans_pr);
/*Create an object with the new style_pr*/
lv_obj_t * obj = lv_obj_create(lv_screen_active());
lv_obj_add_style(obj, &style_def, 0);
lv_obj_add_style(obj, &style_pr, LV_STATE_PRESSED);
lv_obj_center(obj);
}
#endif
Using multiple styles
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_IMAGE
/**
* Using multiple styles
*/
void lv_example_style_11(void)
{
/*A base style*/
static lv_style_t style_base;
lv_style_init(&style_base);
lv_style_set_bg_color(&style_base, lv_palette_main(LV_PALETTE_LIGHT_BLUE));
lv_style_set_border_color(&style_base, lv_palette_darken(LV_PALETTE_LIGHT_BLUE, 3));
lv_style_set_border_width(&style_base, 2);
lv_style_set_radius(&style_base, 10);
lv_style_set_shadow_width(&style_base, 10);
lv_style_set_shadow_offset_y(&style_base, 5);
lv_style_set_shadow_opa(&style_base, LV_OPA_50);
lv_style_set_text_color(&style_base, lv_color_white());
lv_style_set_width(&style_base, 100);
lv_style_set_height(&style_base, LV_SIZE_CONTENT);
/*Set only the properties that should be different*/
static lv_style_t style_warning;
lv_style_init(&style_warning);
lv_style_set_bg_color(&style_warning, lv_palette_main(LV_PALETTE_YELLOW));
lv_style_set_border_color(&style_warning, lv_palette_darken(LV_PALETTE_YELLOW, 3));
lv_style_set_text_color(&style_warning, lv_palette_darken(LV_PALETTE_YELLOW, 4));
/*Create an object with the base style only*/
lv_obj_t * obj_base = lv_obj_create(lv_screen_active());
lv_obj_add_style(obj_base, &style_base, 0);
lv_obj_align(obj_base, LV_ALIGN_LEFT_MID, 20, 0);
lv_obj_t * label = lv_label_create(obj_base);
lv_label_set_text(label, "Base");
lv_obj_center(label);
/*Create another object with the base style and earnings style too*/
lv_obj_t * obj_warning = lv_obj_create(lv_screen_active());
lv_obj_add_style(obj_warning, &style_base, 0);
lv_obj_add_style(obj_warning, &style_warning, 0);
lv_obj_align(obj_warning, LV_ALIGN_RIGHT_MID, -20, 0);
label = lv_label_create(obj_warning);
lv_label_set_text(label, "Warning");
lv_obj_center(label);
}
#endif
Local styles
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_IMAGE
/**
* Local styles
*/
void lv_example_style_12(void)
{
static lv_style_t style;
lv_style_init(&style);
lv_style_set_bg_color(&style, lv_palette_main(LV_PALETTE_GREEN));
lv_style_set_border_color(&style, lv_palette_lighten(LV_PALETTE_GREEN, 3));
lv_style_set_border_width(&style, 3);
lv_obj_t * obj = lv_obj_create(lv_screen_active());
lv_obj_add_style(obj, &style, 0);
/*Overwrite the background color locally*/
lv_obj_set_style_bg_color(obj, lv_palette_main(LV_PALETTE_ORANGE), LV_PART_MAIN);
lv_obj_center(obj);
}
#endif
Add styles to parts and states
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_IMAGE
/**
* Add styles to parts and states
*/
void lv_example_style_13(void)
{
static lv_style_t style_indic;
lv_style_init(&style_indic);
lv_style_set_bg_color(&style_indic, lv_palette_lighten(LV_PALETTE_RED, 3));
lv_style_set_bg_grad_color(&style_indic, lv_palette_main(LV_PALETTE_RED));
lv_style_set_bg_grad_dir(&style_indic, LV_GRAD_DIR_HOR);
static lv_style_t style_indic_pr;
lv_style_init(&style_indic_pr);
lv_style_set_shadow_color(&style_indic_pr, lv_palette_main(LV_PALETTE_RED));
lv_style_set_shadow_width(&style_indic_pr, 10);
lv_style_set_shadow_spread(&style_indic_pr, 3);
/*Create an object with the new style_pr*/
lv_obj_t * obj = lv_slider_create(lv_screen_active());
lv_obj_add_style(obj, &style_indic, LV_PART_INDICATOR);
lv_obj_add_style(obj, &style_indic_pr, LV_PART_INDICATOR | LV_STATE_PRESSED);
lv_slider_set_value(obj, 70, LV_ANIM_OFF);
lv_obj_center(obj);
}
#endif
Extending the current theme
C code
View on GitHub#include "../../src/themes/lv_theme_private.h"
#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_IMAGE
static lv_style_t style_btn;
/*Will be called when the styles of the base theme are already added
to add new styles*/
static void new_theme_apply_cb(lv_theme_t * th, lv_obj_t * obj)
{
LV_UNUSED(th);
if(lv_obj_check_type(obj, &lv_button_class)) {
lv_obj_add_style(obj, &style_btn, 0);
}
}
static void new_theme_init_and_set(void)
{
/*Initialize the styles*/
lv_style_init(&style_btn);
lv_style_set_bg_color(&style_btn, lv_palette_main(LV_PALETTE_GREEN));
lv_style_set_border_color(&style_btn, lv_palette_darken(LV_PALETTE_GREEN, 3));
lv_style_set_border_width(&style_btn, 3);
/*Initialize the new theme from the current theme*/
lv_theme_t * th_act = lv_display_get_theme(NULL);
static lv_theme_t th_new;
th_new = *th_act;
/*Set the parent theme and the style apply callback for the new theme*/
lv_theme_set_parent(&th_new, th_act);
lv_theme_set_apply_cb(&th_new, new_theme_apply_cb);
/*Assign the new theme to the current display*/
lv_display_set_theme(NULL, &th_new);
}
/**
* Extending the current theme
*/
void lv_example_style_14(void)
{
lv_obj_t * btn;
lv_obj_t * label;
btn = lv_button_create(lv_screen_active());
lv_obj_align(btn, LV_ALIGN_TOP_MID, 0, 20);
label = lv_label_create(btn);
lv_label_set_text(label, "Original theme");
new_theme_init_and_set();
btn = lv_button_create(lv_screen_active());
lv_obj_align(btn, LV_ALIGN_BOTTOM_MID, 0, -20);
label = lv_label_create(btn);
lv_label_set_text(label, "New theme");
}
#endif
Opacity and Transformations
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_BUTTON && LV_USE_LABEL
/**
* Opacity and Transformations
*/
void lv_example_style_15(void)
{
lv_obj_t * btn;
lv_obj_t * label;
/*Normal button*/
btn = lv_button_create(lv_screen_active());
lv_obj_set_size(btn, 100, 40);
lv_obj_align(btn, LV_ALIGN_CENTER, 0, -70);
label = lv_label_create(btn);
lv_label_set_text(label, "Normal");
lv_obj_center(label);
/*Set opacity
*The button and the label is rendered to a layer first and that layer is blended*/
btn = lv_button_create(lv_screen_active());
lv_obj_set_size(btn, 100, 40);
lv_obj_set_style_opa(btn, LV_OPA_50, 0);
lv_obj_align(btn, LV_ALIGN_CENTER, 0, 0);
label = lv_label_create(btn);
lv_label_set_text(label, "Opa:50%");
lv_obj_center(label);
/*Set transformations
*The button and the label is rendered to a layer first and that layer is transformed*/
btn = lv_button_create(lv_screen_active());
lv_obj_set_size(btn, 100, 40);
lv_obj_set_style_transform_rotation(btn, 150, 0); /*15 deg*/
lv_obj_set_style_transform_scale(btn, 256 + 64, 0); /*1.25x*/
lv_obj_set_style_transform_pivot_x(btn, 50, 0);
lv_obj_set_style_transform_pivot_y(btn, 20, 0);
lv_obj_set_style_opa(btn, LV_OPA_50, 0);
lv_obj_align(btn, LV_ALIGN_CENTER, 0, 70);
label = lv_label_create(btn);
lv_label_set_text(label, "Transf.");
lv_obj_center(label);
}
#endif
Metallic knob with conic gradient
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES
#if LV_USE_DRAW_SW_COMPLEX_GRADIENTS
/**
* Simulate metallic knob using conical gradient
* For best effect set LV_GRADIENT_MAX_STOPS to 8 or at least 3
*/
void lv_example_style_16(void)
{
#if LV_GRADIENT_MAX_STOPS >= 8
static const lv_color_t grad_colors[8] = {
LV_COLOR_MAKE(0xe8, 0xe8, 0xe8),
LV_COLOR_MAKE(0xff, 0xff, 0xff),
LV_COLOR_MAKE(0xfa, 0xfa, 0xfa),
LV_COLOR_MAKE(0x79, 0x79, 0x79),
LV_COLOR_MAKE(0x48, 0x48, 0x48),
LV_COLOR_MAKE(0x4b, 0x4b, 0x4b),
LV_COLOR_MAKE(0x70, 0x70, 0x70),
LV_COLOR_MAKE(0xe8, 0xe8, 0xe8),
};
#elif LV_GRADIENT_MAX_STOPS >= 3
static const lv_color_t grad_colors[3] = {
LV_COLOR_MAKE(0xe8, 0xe8, 0xe8),
LV_COLOR_MAKE(0xff, 0xff, 0xff),
LV_COLOR_MAKE(0x79, 0x79, 0x79),
};
#else
static const lv_color_t grad_colors[2] = {
LV_COLOR_MAKE(0xe8, 0xe8, 0xe8),
LV_COLOR_MAKE(0x79, 0x79, 0x79),
};
#endif
/*Create a style with gradient background and shadow*/
static lv_style_t style;
lv_style_init(&style);
lv_style_set_radius(&style, 500);
lv_style_set_bg_opa(&style, LV_OPA_COVER);
lv_style_set_shadow_color(&style, lv_color_black());
lv_style_set_shadow_width(&style, 50);
lv_style_set_shadow_offset_x(&style, 20);
lv_style_set_shadow_offset_y(&style, 20);
lv_style_set_shadow_opa(&style, LV_OPA_50);
/*First define a color gradient. In this example we use a gray color map with random values.*/
static lv_grad_dsc_t grad;
lv_gradient_init_stops(&grad, grad_colors, NULL, NULL, sizeof(grad_colors) / sizeof(lv_color_t));
/*Make a conical gradient with the center in the middle of the object*/
#if LV_GRADIENT_MAX_STOPS >= 8
lv_grad_conical_init(&grad, LV_GRAD_CENTER, LV_GRAD_CENTER, 0, 120, LV_GRAD_EXTEND_REFLECT);
#elif LV_GRADIENT_MAX_STOPS >= 3
lv_grad_conical_init(&grad, LV_GRAD_CENTER, LV_GRAD_CENTER, 45, 125, LV_GRAD_EXTEND_REFLECT);
#else
lv_grad_conical_init(&grad, LV_GRAD_CENTER, LV_GRAD_CENTER, 45, 110, LV_GRAD_EXTEND_REFLECT);
#endif
/*Set gradient as background*/
lv_style_set_bg_grad(&style, &grad);
/*Create an object with the new style*/
lv_obj_t * obj = lv_obj_create(lv_screen_active());
lv_obj_add_style(obj, &style, 0);
lv_obj_set_size(obj, 200, 200);
lv_obj_center(obj);
}
#else
void lv_example_style_16(void)
{
lv_obj_t * label = lv_label_create(lv_screen_active());
lv_obj_set_width(label, LV_PCT(80));
lv_label_set_text(label, "LV_USE_DRAW_SW_COMPLEX_GRADIENTS is not enabled");
lv_label_set_long_mode(label, LV_LABEL_LONG_SCROLL_CIRCULAR);
lv_obj_center(label);
}
#endif /*LV_USE_DRAW_SW_COMPLEX_GRADIENTS*/
#endif /*LV_BUILD_EXAMPLES*/
Radial gradient as background
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES
#if LV_USE_DRAW_SW_COMPLEX_GRADIENTS
/**
* Using radial gradient as background
*/
void lv_example_style_17(void)
{
static const lv_color_t grad_colors[2] = {
LV_COLOR_MAKE(0x9B, 0x18, 0x42),
LV_COLOR_MAKE(0x00, 0x00, 0x00),
};
int32_t width = lv_display_get_horizontal_resolution(NULL);
int32_t height = lv_display_get_vertical_resolution(NULL);
static lv_style_t style;
lv_style_init(&style);
/*First define a color gradient. In this example we use a purple to black color map.*/
static lv_grad_dsc_t grad;
lv_gradient_init_stops(&grad, grad_colors, NULL, NULL, sizeof(grad_colors) / sizeof(lv_color_t));
/*Make a radial gradient with the center in the middle of the object, extending to the farthest corner*/
lv_grad_radial_init(&grad, LV_GRAD_CENTER, LV_GRAD_CENTER, LV_GRAD_RIGHT, LV_GRAD_BOTTOM, LV_GRAD_EXTEND_PAD);
/*Set gradient as background*/
lv_style_set_bg_grad(&style, &grad);
/*Create an object with the new style*/
lv_obj_t * obj = lv_obj_create(lv_screen_active());
lv_obj_add_style(obj, &style, 0);
lv_obj_set_size(obj, width, height);
lv_obj_center(obj);
}
#else
void lv_example_style_17(void)
{
lv_obj_t * label = lv_label_create(lv_screen_active());
lv_obj_set_width(label, LV_PCT(80));
lv_label_set_text(label, "LV_USE_DRAW_SW_COMPLEX_GRADIENTS is not enabled");
lv_label_set_long_mode(label, LV_LABEL_LONG_SCROLL_CIRCULAR);
lv_obj_center(label);
}
#endif /*LV_USE_DRAW_SW_COMPLEX_GRADIENTS*/
#endif /*LV_BUILD_EXAMPLES*/
Animations（动画）
Start animation on an event
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_SWITCH
static void anim_x_cb(void * var, int32_t v)
{
lv_obj_set_x(var, v);
}
static void sw_event_cb(lv_event_t * e)
{
lv_obj_t * sw = lv_event_get_target(e);
lv_obj_t * label = lv_event_get_user_data(e);
if(lv_obj_has_state(sw, LV_STATE_CHECKED)) {
lv_anim_t a;
lv_anim_init(&a);
lv_anim_set_var(&a, label);
lv_anim_set_values(&a, lv_obj_get_x(label), 100);
lv_anim_set_duration(&a, 500);
lv_anim_set_exec_cb(&a, anim_x_cb);
lv_anim_set_path_cb(&a, lv_anim_path_overshoot);
lv_anim_start(&a);
}
else {
lv_anim_t a;
lv_anim_init(&a);
lv_anim_set_var(&a, label);
lv_anim_set_values(&a, lv_obj_get_x(label), -lv_obj_get_width(label));
lv_anim_set_duration(&a, 500);
lv_anim_set_exec_cb(&a, anim_x_cb);
lv_anim_set_path_cb(&a, lv_anim_path_ease_in);
lv_anim_start(&a);
}
}
/**
* Start animation on an event
*/
void lv_example_anim_1(void)
{
lv_obj_t * label = lv_label_create(lv_screen_active());
lv_label_set_text(label, "Hello animations!");
lv_obj_set_pos(label, 100, 10);
lv_obj_t * sw = lv_switch_create(lv_screen_active());
lv_obj_center(sw);
lv_obj_add_state(sw, LV_STATE_CHECKED);
lv_obj_add_event_cb(sw, sw_event_cb, LV_EVENT_VALUE_CHANGED, label);
}
#endif
Playback animation
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_SWITCH
static void anim_x_cb(void * var, int32_t v)
{
lv_obj_set_x(var, v);
}
static void anim_size_cb(void * var, int32_t v)
{
lv_obj_set_size(var, v, v);
}
/**
* Create a playback animation
*/
void lv_example_anim_2(void)
{
lv_obj_t * obj = lv_obj_create(lv_screen_active());
lv_obj_set_style_bg_color(obj, lv_palette_main(LV_PALETTE_RED), 0);
lv_obj_set_style_radius(obj, LV_RADIUS_CIRCLE, 0);
lv_obj_align(obj, LV_ALIGN_LEFT_MID, 10, 0);
lv_anim_t a;
lv_anim_init(&a);
lv_anim_set_var(&a, obj);
lv_anim_set_values(&a, 10, 50);
lv_anim_set_duration(&a, 1000);
lv_anim_set_playback_delay(&a, 100);
lv_anim_set_playback_duration(&a, 300);
lv_anim_set_repeat_delay(&a, 500);
lv_anim_set_repeat_count(&a, LV_ANIM_REPEAT_INFINITE);
lv_anim_set_path_cb(&a, lv_anim_path_ease_in_out);
lv_anim_set_exec_cb(&a, anim_size_cb);
lv_anim_start(&a);
lv_anim_set_exec_cb(&a, anim_x_cb);
lv_anim_set_values(&a, 10, 240);
lv_anim_start(&a);
}
#endif
Cubic Bezier animation
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_SLIDER && LV_USE_CHART && LV_USE_BUTTON && LV_USE_GRID
/**
* the example show the use of cubic-bezier3 in animation.
* the control point P1,P2 of cubic-bezier3 can be adjusted by slider.
* and the chart shows the cubic-bezier3 in real time. you can click
* run button see animation in current point of cubic-bezier3.
*/
#define CHART_POINTS_NUM 256
struct {
lv_obj_t * anim_obj;
lv_obj_t * chart;
lv_chart_series_t * ser1;
lv_obj_t * p1_slider;
lv_obj_t * p1_label;
lv_obj_t * p2_slider;
lv_obj_t * p2_label;
lv_obj_t * run_btn;
uint16_t p1;
uint16_t p2;
lv_anim_t a;
} ginfo;
static int32_t anim_path_bezier3_cb(const lv_anim_t * a);
static void refer_chart_cubic_bezier(void);
static void run_button_event_handler(lv_event_t * e);
static void slider_event_cb(lv_event_t * e);
static void page_obj_init(lv_obj_t * par);
static void anim_x_cb(void * var, int32_t v);
/**
* create an animation
*/
void lv_example_anim_3(void)
{
static int32_t col_dsc[] = {LV_GRID_FR(1), 200, LV_GRID_FR(1), LV_GRID_TEMPLATE_LAST};
static int32_t row_dsc[] = {30, 10, 10, LV_GRID_FR(1), LV_GRID_TEMPLATE_LAST};
/*Create a container with grid*/
lv_obj_t * cont = lv_obj_create(lv_screen_active());
lv_obj_set_style_pad_all(cont, 2, LV_PART_MAIN);
lv_obj_set_style_pad_column(cont, 10, LV_PART_MAIN);
lv_obj_set_style_pad_row(cont, 10, LV_PART_MAIN);
lv_obj_set_grid_dsc_array(cont, col_dsc, row_dsc);
lv_obj_set_size(cont, 320, 240);
lv_obj_center(cont);
page_obj_init(cont);
lv_anim_init(&ginfo.a);
lv_anim_set_var(&ginfo.a, ginfo.anim_obj);
int32_t end = lv_obj_get_style_width(cont, LV_PART_MAIN) -
lv_obj_get_style_width(ginfo.anim_obj, LV_PART_MAIN) - 10;
lv_anim_set_values(&ginfo.a, 5, end);
lv_anim_set_duration(&ginfo.a, 2000);
lv_anim_set_exec_cb(&ginfo.a, anim_x_cb);
lv_anim_set_path_cb(&ginfo.a, anim_path_bezier3_cb);
refer_chart_cubic_bezier();
}
static int32_t anim_path_bezier3_cb(const lv_anim_t * a)
{
uint32_t t = lv_map(a->act_time, 0, a->duration, 0, 1024);
int32_t step = lv_bezier3(t, 0, ginfo.p1, ginfo.p2, 1024);
int32_t new_value;
new_value = step * (a->end_value - a->start_value);
new_value = new_value >> 10;
new_value += a->start_value;
return new_value;
}
static void refer_chart_cubic_bezier(void)
{
for(uint16_t i = 0; i <= CHART_POINTS_NUM; i ++) {
uint32_t t = i * (1024 / CHART_POINTS_NUM);
int32_t step = lv_bezier3(t, 0, ginfo.p1, ginfo.p2, 1024);
lv_chart_set_value_by_id2(ginfo.chart, ginfo.ser1, i, t, step);
}
lv_chart_refresh(ginfo.chart);
}
static void anim_x_cb(void * var, int32_t v)
{
lv_obj_set_style_translate_x(var, v, LV_PART_MAIN);
}
static void run_button_event_handler(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
if(code == LV_EVENT_CLICKED) {
lv_anim_start(&ginfo.a);
}
}
static void slider_event_cb(lv_event_t * e)
{
char buf[16];
lv_obj_t * label;
lv_obj_t * slider = lv_event_get_target(e);
if(slider == ginfo.p1_slider) {
label = ginfo.p1_label;
ginfo.p1 = lv_slider_get_value(slider);
lv_snprintf(buf, sizeof(buf), "p1:%d", ginfo.p1);
}
else {
label = ginfo.p2_label;
ginfo.p2 = lv_slider_get_value(slider);
lv_snprintf(buf, sizeof(buf), "p2:%d", ginfo.p2);
}
lv_label_set_text(label, buf);
refer_chart_cubic_bezier();
}
static void page_obj_init(lv_obj_t * par)
{
ginfo.anim_obj = lv_obj_create(par);
lv_obj_set_size(ginfo.anim_obj, 30, 30);
lv_obj_set_align(ginfo.anim_obj, LV_ALIGN_TOP_LEFT);
lv_obj_remove_flag(ginfo.anim_obj, LV_OBJ_FLAG_SCROLLABLE);
lv_obj_set_style_bg_color(ginfo.anim_obj, lv_palette_main(LV_PALETTE_RED), LV_PART_MAIN);
lv_obj_set_grid_cell(ginfo.anim_obj, LV_GRID_ALIGN_START, 0, 1, LV_GRID_ALIGN_START, 0, 1);
ginfo.p1_label = lv_label_create(par);
ginfo.p2_label = lv_label_create(par);
lv_label_set_text(ginfo.p1_label, "p1:0");
lv_label_set_text(ginfo.p2_label, "p2:0");
lv_obj_set_grid_cell(ginfo.p1_label, LV_GRID_ALIGN_START, 0, 1, LV_GRID_ALIGN_START, 1, 1);
lv_obj_set_grid_cell(ginfo.p2_label, LV_GRID_ALIGN_START, 0, 1, LV_GRID_ALIGN_START, 2, 1);
ginfo.p1_slider = lv_slider_create(par);
ginfo.p2_slider = lv_slider_create(par);
lv_slider_set_range(ginfo.p1_slider, 0, 1024);
lv_slider_set_range(ginfo.p2_slider, 0, 1024);
lv_obj_set_style_pad_all(ginfo.p1_slider, 2, LV_PART_KNOB);
lv_obj_set_style_pad_all(ginfo.p2_slider, 2, LV_PART_KNOB);
lv_obj_add_event_cb(ginfo.p1_slider, slider_event_cb, LV_EVENT_VALUE_CHANGED, NULL);
lv_obj_add_event_cb(ginfo.p2_slider, slider_event_cb, LV_EVENT_VALUE_CHANGED, NULL);
lv_obj_set_grid_cell(ginfo.p1_slider, LV_GRID_ALIGN_STRETCH, 1, 1, LV_GRID_ALIGN_START, 1, 1);
lv_obj_set_grid_cell(ginfo.p2_slider, LV_GRID_ALIGN_STRETCH, 1, 1, LV_GRID_ALIGN_START, 2, 1);
ginfo.run_btn = lv_button_create(par);
lv_obj_add_event_cb(ginfo.run_btn, run_button_event_handler, LV_EVENT_CLICKED, NULL);
lv_obj_t * btn_label = lv_label_create(ginfo.run_btn);
lv_label_set_text(btn_label, LV_SYMBOL_PLAY);
lv_obj_center(btn_label);
lv_obj_set_grid_cell(ginfo.run_btn, LV_GRID_ALIGN_STRETCH, 2, 1, LV_GRID_ALIGN_STRETCH, 1, 2);
ginfo.chart = lv_chart_create(par);
lv_obj_set_style_pad_all(ginfo.chart, 0, LV_PART_MAIN);
lv_obj_set_style_size(ginfo.chart, 0, 0, LV_PART_INDICATOR);
lv_chart_set_type(ginfo.chart, LV_CHART_TYPE_SCATTER);
ginfo.ser1 = lv_chart_add_series(ginfo.chart, lv_palette_main(LV_PALETTE_RED), LV_CHART_AXIS_PRIMARY_Y);
lv_chart_set_range(ginfo.chart, LV_CHART_AXIS_PRIMARY_Y, 0, 1024);
lv_chart_set_range(ginfo.chart, LV_CHART_AXIS_PRIMARY_X, 0, 1024);
lv_chart_set_point_count(ginfo.chart, CHART_POINTS_NUM);
lv_obj_set_grid_cell(ginfo.chart, LV_GRID_ALIGN_STRETCH, 0, 3, LV_GRID_ALIGN_STRETCH, 3, 1);
}
#endif
Animation timeline
C code
View on GitHub#include "../lv_examples.h"
#if LV_USE_FLEX && LV_BUILD_EXAMPLES
static const int32_t obj_width = 90;
static const int32_t obj_height = 70;
static void set_width(lv_anim_t * var, int32_t v)
{
lv_obj_set_width(var->var, v);
}
static void set_height(lv_anim_t * var, int32_t v)
{
lv_obj_set_height(var->var, v);
}
static void set_slider_value(lv_anim_t * var, int32_t v)
{
lv_slider_set_value(var->var, v, LV_ANIM_OFF);
}
static void btn_start_event_handler(lv_event_t * e)
{
lv_obj_t * btn = lv_event_get_current_target_obj(e);
lv_anim_timeline_t * anim_timeline = lv_event_get_user_data(e);
bool reverse = lv_obj_has_state(btn, LV_STATE_CHECKED);
lv_anim_timeline_set_reverse(anim_timeline, reverse);
lv_anim_timeline_start(anim_timeline);
}
static void btn_pause_event_handler(lv_event_t * e)
{
lv_anim_timeline_t * anim_timeline = lv_event_get_user_data(e);
lv_anim_timeline_pause(anim_timeline);
}
static void slider_prg_event_handler(lv_event_t * e)
{
lv_obj_t * slider = lv_event_get_current_target_obj(e);
lv_anim_timeline_t * anim_timeline = lv_event_get_user_data(e);
int32_t progress = lv_slider_get_value(slider);
lv_anim_timeline_set_progress(anim_timeline, progress);
}
/**
* Create an animation timeline
*/
void lv_example_anim_timeline_1(void)
{
/* Create anim timeline */
lv_anim_timeline_t * anim_timeline = lv_anim_timeline_create();
lv_obj_t * par = lv_screen_active();
lv_obj_set_flex_flow(par, LV_FLEX_FLOW_ROW);
lv_obj_set_flex_align(par, LV_FLEX_ALIGN_SPACE_AROUND, LV_FLEX_ALIGN_CENTER, LV_FLEX_ALIGN_CENTER);
/* create btn_start */
lv_obj_t * btn_start = lv_button_create(par);
lv_obj_add_event_cb(btn_start, btn_start_event_handler, LV_EVENT_VALUE_CHANGED, anim_timeline);
lv_obj_add_flag(btn_start, LV_OBJ_FLAG_IGNORE_LAYOUT);
lv_obj_add_flag(btn_start, LV_OBJ_FLAG_CHECKABLE);
lv_obj_align(btn_start, LV_ALIGN_TOP_MID, -100, 20);
lv_obj_t * label_start = lv_label_create(btn_start);
lv_label_set_text(label_start, "Start");
lv_obj_center(label_start);
/* create btn_pause */
lv_obj_t * btn_pause = lv_button_create(par);
lv_obj_add_event_cb(btn_pause, btn_pause_event_handler, LV_EVENT_CLICKED, anim_timeline);
lv_obj_add_flag(btn_pause, LV_OBJ_FLAG_IGNORE_LAYOUT);
lv_obj_align(btn_pause, LV_ALIGN_TOP_MID, 100, 20);
lv_obj_t * label_pause = lv_label_create(btn_pause);
lv_label_set_text(label_pause, "Pause");
lv_obj_center(label_pause);
/* create slider_prg */
lv_obj_t * slider_prg = lv_slider_create(par);
lv_obj_add_event_cb(slider_prg, slider_prg_event_handler, LV_EVENT_VALUE_CHANGED, anim_timeline);
lv_obj_add_flag(slider_prg, LV_OBJ_FLAG_IGNORE_LAYOUT);
lv_obj_align(slider_prg, LV_ALIGN_BOTTOM_MID, 0, -20);
lv_slider_set_range(slider_prg, 0, LV_ANIM_TIMELINE_PROGRESS_MAX);
/* create 3 objects */
lv_obj_t * obj1 = lv_obj_create(par);
lv_obj_set_size(obj1, obj_width, obj_height);
lv_obj_set_scrollbar_mode(obj1, LV_SCROLLBAR_MODE_OFF);
lv_obj_t * obj2 = lv_obj_create(par);
lv_obj_set_size(obj2, obj_width, obj_height);
lv_obj_set_scrollbar_mode(obj2, LV_SCROLLBAR_MODE_OFF);
lv_obj_t * obj3 = lv_obj_create(par);
lv_obj_set_size(obj3, obj_width, obj_height);
lv_obj_set_scrollbar_mode(obj3, LV_SCROLLBAR_MODE_OFF);
/* anim-slider */
lv_anim_t a_slider;
lv_anim_init(&a_slider);
lv_anim_set_var(&a_slider, slider_prg);
lv_anim_set_values(&a_slider, 0, LV_ANIM_TIMELINE_PROGRESS_MAX);
lv_anim_set_custom_exec_cb(&a_slider, set_slider_value);
lv_anim_set_path_cb(&a_slider, lv_anim_path_linear);
lv_anim_set_duration(&a_slider, 700);
/* anim-obj1 */
lv_anim_t a1;
lv_anim_init(&a1);
lv_anim_set_var(&a1, obj1);
lv_anim_set_values(&a1, 0, obj_width);
lv_anim_set_custom_exec_cb(&a1, set_width);
lv_anim_set_path_cb(&a1, lv_anim_path_overshoot);
lv_anim_set_duration(&a1, 300);
lv_anim_t a2;
lv_anim_init(&a2);
lv_anim_set_var(&a2, obj1);
lv_anim_set_values(&a2, 0, obj_height);
lv_anim_set_custom_exec_cb(&a2, set_height);
lv_anim_set_path_cb(&a2, lv_anim_path_ease_out);
lv_anim_set_duration(&a2, 300);
/* anim-obj2 */
lv_anim_t a3;
lv_anim_init(&a3);
lv_anim_set_var(&a3, obj2);
lv_anim_set_values(&a3, 0, obj_width);
lv_anim_set_custom_exec_cb(&a3, set_width);
lv_anim_set_path_cb(&a3, lv_anim_path_overshoot);
lv_anim_set_duration(&a3, 300);
lv_anim_t a4;
lv_anim_init(&a4);
lv_anim_set_var(&a4, obj2);
lv_anim_set_values(&a4, 0, obj_height);
lv_anim_set_custom_exec_cb(&a4, set_height);
lv_anim_set_path_cb(&a4, lv_anim_path_ease_out);
lv_anim_set_duration(&a4, 300);
/* anim-obj3 */
lv_anim_t a5;
lv_anim_init(&a5);
lv_anim_set_var(&a5, obj3);
lv_anim_set_values(&a5, 0, obj_width);
lv_anim_set_custom_exec_cb(&a5, set_width);
lv_anim_set_path_cb(&a5, lv_anim_path_overshoot);
lv_anim_set_duration(&a5, 300);
lv_anim_t a6;
lv_anim_init(&a6);
lv_anim_set_var(&a6, obj3);
lv_anim_set_values(&a6, 0, obj_height);
lv_anim_set_custom_exec_cb(&a6, set_height);
lv_anim_set_path_cb(&a6, lv_anim_path_ease_out);
lv_anim_set_duration(&a6, 300);
/* add animations to timeline */
lv_anim_timeline_add(anim_timeline, 0, &a_slider);
lv_anim_timeline_add(anim_timeline, 0, &a1);
lv_anim_timeline_add(anim_timeline, 0, &a2);
lv_anim_timeline_add(anim_timeline, 200, &a3);
lv_anim_timeline_add(anim_timeline, 200, &a4);
lv_anim_timeline_add(anim_timeline, 400, &a5);
lv_anim_timeline_add(anim_timeline, 400, &a6);
lv_anim_timeline_set_progress(anim_timeline, LV_ANIM_TIMELINE_PROGRESS_MAX);
}
#endif
Events（事件）
Click streaks
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_LABEL
static void short_click_event_cb(lv_event_t * e)
{
LV_LOG_USER("Short clicked");
lv_obj_t * info_label = lv_event_get_user_data(e);
lv_indev_t * indev = lv_event_get_param(e);
uint8_t cnt = lv_indev_get_short_click_streak(indev);
lv_label_set_text_fmt(info_label, "Short click streak: %u", cnt);
}
static void streak_event_cb(lv_event_t * e)
{
lv_obj_t * btn = lv_event_get_target(e);
lv_obj_t * label = lv_obj_get_child(btn, 0);
const char * text = lv_event_get_user_data(e);
lv_label_set_text(label, text);
}
void lv_example_event_streak(void)
{
lv_obj_t * info_label = lv_label_create(lv_screen_active());
lv_label_set_text(info_label, "No events yet");
lv_obj_t * btn = lv_button_create(lv_screen_active());
lv_obj_set_size(btn, 100, 50);
lv_obj_center(btn);
lv_obj_add_event_cb(btn, short_click_event_cb, LV_EVENT_SHORT_CLICKED, info_label);
lv_obj_add_event_cb(btn, streak_event_cb, LV_EVENT_SINGLE_CLICKED, "Single clicked");
lv_obj_add_event_cb(btn, streak_event_cb, LV_EVENT_DOUBLE_CLICKED, "Double clicked");
lv_obj_add_event_cb(btn, streak_event_cb, LV_EVENT_TRIPLE_CLICKED, "Triple clicked");
lv_obj_t * label = lv_label_create(btn);
lv_label_set_text(label, "Click me!");
lv_obj_center(label);
}
#endif
Handle multiple events
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_SWITCH
static void event_cb(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * label = lv_event_get_user_data(e);
switch(code) {
case LV_EVENT_PRESSED:
lv_label_set_text(label, "The last button event:\nLV_EVENT_PRESSED");
break;
case LV_EVENT_CLICKED:
lv_label_set_text(label, "The last button event:\nLV_EVENT_CLICKED");
break;
case LV_EVENT_LONG_PRESSED:
lv_label_set_text(label, "The last button event:\nLV_EVENT_LONG_PRESSED");
break;
case LV_EVENT_LONG_PRESSED_REPEAT:
lv_label_set_text(label, "The last button event:\nLV_EVENT_LONG_PRESSED_REPEAT");
break;
default:
break;
}
}
/**
* Handle multiple events
*/
void lv_example_event_button(void)
{
lv_obj_t * btn = lv_button_create(lv_screen_active());
lv_obj_set_size(btn, 100, 50);
lv_obj_center(btn);
lv_obj_t * btn_label = lv_label_create(btn);
lv_label_set_text(btn_label, "Click me!");
lv_obj_center(btn_label);
lv_obj_t * info_label = lv_label_create(lv_screen_active());
lv_label_set_text(info_label, "The last button event:\nNone");
lv_obj_add_event_cb(btn, event_cb, LV_EVENT_ALL, info_label);
}
#endif
Event bubbling
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_FLEX
static void event_cb(lv_event_t * e)
{
/*The original target of the event. Can be the buttons or the container*/
lv_obj_t * target = lv_event_get_target(e);
/*The current target is always the container as the event is added to it*/
lv_obj_t * cont = lv_event_get_current_target(e);
/*If container was clicked do nothing*/
if(target == cont) return;
/*Make the clicked buttons red*/
lv_obj_set_style_bg_color(target, lv_palette_main(LV_PALETTE_RED), 0);
}
/**
* Demonstrate event bubbling
*/
void lv_example_event_bubble(void)
{
lv_obj_t * cont = lv_obj_create(lv_screen_active());
lv_obj_set_size(cont, 290, 200);
lv_obj_center(cont);
lv_obj_set_flex_flow(cont, LV_FLEX_FLOW_ROW_WRAP);
uint32_t i;
for(i = 0; i < 30; i++) {
lv_obj_t * btn = lv_button_create(cont);
lv_obj_set_size(btn, 70, 50);
lv_obj_add_flag(btn, LV_OBJ_FLAG_EVENT_BUBBLE);
lv_obj_t * label = lv_label_create(btn);
lv_label_set_text_fmt(label, "%"LV_PRIu32, i);
lv_obj_center(label);
}
lv_obj_add_event_cb(cont, event_cb, LV_EVENT_CLICKED, NULL);
}
#endif
Draw event
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES
static uint32_t size = 0;
static bool size_dec = false;
static void timer_cb(lv_timer_t * timer)
{
lv_obj_invalidate(lv_timer_get_user_data(timer));
if(size_dec) size--;
else size++;
if(size == 50) size_dec = true;
else if(size == 0) size_dec = false;
}
static void event_cb(lv_event_t * e)
{
lv_obj_t * obj = lv_event_get_target(e);
lv_draw_task_t * draw_task = lv_event_get_draw_task(e);
lv_draw_dsc_base_t * base_dsc = lv_draw_task_get_draw_dsc(draw_task);
if(base_dsc->part == LV_PART_MAIN) {
lv_draw_rect_dsc_t draw_dsc;
lv_draw_rect_dsc_init(&draw_dsc);
draw_dsc.bg_color = lv_color_hex(0xffaaaa);
draw_dsc.radius = LV_RADIUS_CIRCLE;
draw_dsc.border_color = lv_color_hex(0xff5555);
draw_dsc.border_width = 2;
draw_dsc.outline_color = lv_color_hex(0xff0000);
draw_dsc.outline_pad = 3;
draw_dsc.outline_width = 2;
lv_area_t a;
a.x1 = 0;
a.y1 = 0;
a.x2 = size;
a.y2 = size;
lv_area_t obj_coords;
lv_obj_get_coords(obj, &obj_coords);
lv_area_align(&obj_coords, &a, LV_ALIGN_CENTER, 0, 0);
lv_draw_rect(base_dsc->layer, &draw_dsc, &a);
}
}
/**
* Demonstrate the usage of draw event
*/
void lv_example_event_draw(void)
{
lv_obj_t * cont = lv_obj_create(lv_screen_active());
lv_obj_set_size(cont, 200, 200);
lv_obj_center(cont);
lv_obj_add_event_cb(cont, event_cb, LV_EVENT_DRAW_TASK_ADDED, NULL);
lv_obj_add_flag(cont, LV_OBJ_FLAG_SEND_DRAW_TASK_EVENTS);
lv_timer_create(timer_cb, 30, cont);
}
#endif
Layouts（布局）
Flex
A simple row and a column layout with flexbox
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_FLEX && LV_BUILD_EXAMPLES
/**
* A simple row and a column layout with flexbox
*/
void lv_example_flex_1(void)
{
/*Create a container with ROW flex direction*/
lv_obj_t * cont_row = lv_obj_create(lv_screen_active());
lv_obj_set_size(cont_row, 300, 75);
lv_obj_align(cont_row, LV_ALIGN_TOP_MID, 0, 5);
lv_obj_set_flex_flow(cont_row, LV_FLEX_FLOW_ROW);
/*Create a container with COLUMN flex direction*/
lv_obj_t * cont_col = lv_obj_create(lv_screen_active());
lv_obj_set_size(cont_col, 200, 150);
lv_obj_align_to(cont_col, cont_row, LV_ALIGN_OUT_BOTTOM_MID, 0, 5);
lv_obj_set_flex_flow(cont_col, LV_FLEX_FLOW_COLUMN);
uint32_t i;
for(i = 0; i < 10; i++) {
lv_obj_t * obj;
lv_obj_t * label;
/*Add items to the row*/
obj = lv_button_create(cont_row);
lv_obj_set_size(obj, 100, LV_PCT(100));
label = lv_label_create(obj);
lv_label_set_text_fmt(label, "Item: %"LV_PRIu32"", i);
lv_obj_center(label);
/*Add items to the column*/
obj = lv_button_create(cont_col);
lv_obj_set_size(obj, LV_PCT(100), LV_SIZE_CONTENT);
label = lv_label_create(obj);
lv_label_set_text_fmt(label, "Item: %"LV_PRIu32, i);
lv_obj_center(label);
}
}
#endif
Arrange items in rows with wrap and even spacing
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_FLEX && LV_BUILD_EXAMPLES
/**
* Arrange items in rows with wrap and place the items to get even space around them.
*/
void lv_example_flex_2(void)
{
static lv_style_t style;
lv_style_init(&style);
lv_style_set_flex_flow(&style, LV_FLEX_FLOW_ROW_WRAP);
lv_style_set_flex_main_place(&style, LV_FLEX_ALIGN_SPACE_EVENLY);
lv_style_set_layout(&style, LV_LAYOUT_FLEX);
lv_obj_t * cont = lv_obj_create(lv_screen_active());
lv_obj_set_size(cont, 300, 220);
lv_obj_center(cont);
lv_obj_add_style(cont, &style, 0);
uint32_t i;
for(i = 0; i < 8; i++) {
lv_obj_t * obj = lv_obj_create(cont);
lv_obj_set_size(obj, 70, LV_SIZE_CONTENT);
lv_obj_add_flag(obj, LV_OBJ_FLAG_CHECKABLE);
lv_obj_t * label = lv_label_create(obj);
lv_label_set_text_fmt(label, "%"LV_PRIu32, i);
lv_obj_center(label);
}
}
#endif
Demonstrate flex grow
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_FLEX && LV_BUILD_EXAMPLES
/**
* Demonstrate flex grow.
*/
void lv_example_flex_3(void)
{
lv_obj_t * cont = lv_obj_create(lv_screen_active());
lv_obj_set_size(cont, 300, 220);
lv_obj_center(cont);
lv_obj_set_flex_flow(cont, LV_FLEX_FLOW_ROW);
lv_obj_t * obj;
obj = lv_obj_create(cont);
lv_obj_set_size(obj, 40, 40); /*Fix size*/
obj = lv_obj_create(cont);
lv_obj_set_height(obj, 40);
lv_obj_set_flex_grow(obj, 1); /*1 portion from the free space*/
obj = lv_obj_create(cont);
lv_obj_set_height(obj, 40);
lv_obj_set_flex_grow(obj, 2); /*2 portion from the free space*/
obj = lv_obj_create(cont);
lv_obj_set_size(obj, 40, 40); /*Fix size. It is flushed to the right by the "grow" items*/
}
#endif
Demonstrate flex grow.
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_FLEX && LV_BUILD_EXAMPLES
/**
* Reverse the order of flex items
*/
void lv_example_flex_4(void)
{
lv_obj_t * cont = lv_obj_create(lv_screen_active());
lv_obj_set_size(cont, 300, 220);
lv_obj_center(cont);
lv_obj_set_flex_flow(cont, LV_FLEX_FLOW_COLUMN_REVERSE);
uint32_t i;
for(i = 0; i < 6; i++) {
lv_obj_t * obj = lv_obj_create(cont);
lv_obj_set_size(obj, 100, 50);
lv_obj_t * label = lv_label_create(obj);
lv_label_set_text_fmt(label, "Item: %"LV_PRIu32, i);
lv_obj_center(label);
}
}
#endif
Demonstrate column and row gap style properties
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_FLEX && LV_BUILD_EXAMPLES
static void row_gap_anim(void * obj, int32_t v)
{
lv_obj_set_style_pad_row(obj, v, 0);
}
static void column_gap_anim(void * obj, int32_t v)
{
lv_obj_set_style_pad_column(obj, v, 0);
}
/**
* Demonstrate the effect of column and row gap style properties
*/
void lv_example_flex_5(void)
{
lv_obj_t * cont = lv_obj_create(lv_screen_active());
lv_obj_set_size(cont, 300, 220);
lv_obj_center(cont);
lv_obj_set_flex_flow(cont, LV_FLEX_FLOW_ROW_WRAP);
uint32_t i;
for(i = 0; i < 9; i++) {
lv_obj_t * obj = lv_obj_create(cont);
lv_obj_set_size(obj, 70, LV_SIZE_CONTENT);
lv_obj_t * label = lv_label_create(obj);
lv_label_set_text_fmt(label, "%"LV_PRIu32, i);
lv_obj_center(label);
}
lv_anim_t a;
lv_anim_init(&a);
lv_anim_set_var(&a, cont);
lv_anim_set_values(&a, 0, 10);
lv_anim_set_repeat_count(&a, LV_ANIM_REPEAT_INFINITE);
lv_anim_set_exec_cb(&a, row_gap_anim);
lv_anim_set_duration(&a, 500);
lv_anim_set_playback_duration(&a, 500);
lv_anim_start(&a);
lv_anim_set_exec_cb(&a, column_gap_anim);
lv_anim_set_duration(&a, 3000);
lv_anim_set_playback_duration(&a, 3000);
lv_anim_start(&a);
}
#endif
RTL base direction changes order of the items
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_FLEX && LV_BUILD_EXAMPLES
/**
* RTL base direction changes order of the items.
* Also demonstrate how horizontal scrolling works with RTL.
*/
void lv_example_flex_6(void)
{
lv_obj_t * cont = lv_obj_create(lv_screen_active());
lv_obj_set_style_base_dir(cont, LV_BASE_DIR_RTL, 0);
lv_obj_set_size(cont, 300, 220);
lv_obj_center(cont);
lv_obj_set_flex_flow(cont, LV_FLEX_FLOW_ROW_WRAP);
uint32_t i;
for(i = 0; i < 20; i++) {
lv_obj_t * obj = lv_obj_create(cont);
lv_obj_set_size(obj, 70, LV_SIZE_CONTENT);
lv_obj_t * label = lv_label_create(obj);
lv_label_set_text_fmt(label, "%"LV_PRIu32, i);
lv_obj_center(label);
}
}
#endif
Grid
A simple grid
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_GRID && LV_BUILD_EXAMPLES
/**
* A simple grid
*/
void lv_example_grid_1(void)
{
static int32_t col_dsc[] = {70, 70, 70, LV_GRID_TEMPLATE_LAST};
static int32_t row_dsc[] = {50, 50, 50, LV_GRID_TEMPLATE_LAST};
/*Create a container with grid*/
lv_obj_t * cont = lv_obj_create(lv_screen_active());
lv_obj_set_style_grid_column_dsc_array(cont, col_dsc, 0);
lv_obj_set_style_grid_row_dsc_array(cont, row_dsc, 0);
lv_obj_set_size(cont, 300, 220);
lv_obj_center(cont);
lv_obj_set_layout(cont, LV_LAYOUT_GRID);
lv_obj_t * label;
lv_obj_t * obj;
uint32_t i;
for(i = 0; i < 9; i++) {
uint8_t col = i % 3;
uint8_t row = i / 3;
obj = lv_button_create(cont);
/*Stretch the cell horizontally and vertically too
*Set span to 1 to make the cell 1 column/row sized*/
lv_obj_set_grid_cell(obj, LV_GRID_ALIGN_STRETCH, col, 1,
LV_GRID_ALIGN_STRETCH, row, 1);
label = lv_label_create(obj);
lv_label_set_text_fmt(label, "c%d, r%d", col, row);
lv_obj_center(label);
}
}
#endif
Demonstrate cell placement and span
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_GRID && LV_BUILD_EXAMPLES
/**
* Demonstrate cell placement and span
*/
void lv_example_grid_2(void)
{
static int32_t col_dsc[] = {70, 70, 70, LV_GRID_TEMPLATE_LAST};
static int32_t row_dsc[] = {50, 50, 50, LV_GRID_TEMPLATE_LAST};
/*Create a container with grid*/
lv_obj_t * cont = lv_obj_create(lv_screen_active());
lv_obj_set_grid_dsc_array(cont, col_dsc, row_dsc);
lv_obj_set_size(cont, 300, 220);
lv_obj_center(cont);
lv_obj_t * label;
lv_obj_t * obj;
/*Cell to 0;0 and align to to the start (left/top) horizontally and vertically too*/
obj = lv_obj_create(cont);
lv_obj_set_size(obj, LV_SIZE_CONTENT, LV_SIZE_CONTENT);
lv_obj_set_grid_cell(obj, LV_GRID_ALIGN_START, 0, 1,
LV_GRID_ALIGN_START, 0, 1);
label = lv_label_create(obj);
lv_label_set_text(label, "c0, r0");
/*Cell to 1;0 and align to to the start (left) horizontally and center vertically too*/
obj = lv_obj_create(cont);
lv_obj_set_size(obj, LV_SIZE_CONTENT, LV_SIZE_CONTENT);
lv_obj_set_grid_cell(obj, LV_GRID_ALIGN_START, 1, 1,
LV_GRID_ALIGN_CENTER, 0, 1);
label = lv_label_create(obj);
lv_label_set_text(label, "c1, r0");
/*Cell to 2;0 and align to to the start (left) horizontally and end (bottom) vertically too*/
obj = lv_obj_create(cont);
lv_obj_set_size(obj, LV_SIZE_CONTENT, LV_SIZE_CONTENT);
lv_obj_set_grid_cell(obj, LV_GRID_ALIGN_START, 2, 1,
LV_GRID_ALIGN_END, 0, 1);
label = lv_label_create(obj);
lv_label_set_text(label, "c2, r0");
/*Cell to 1;1 but 2 column wide (span = 2).Set width and height to stretched.*/
obj = lv_obj_create(cont);
lv_obj_set_size(obj, LV_SIZE_CONTENT, LV_SIZE_CONTENT);
lv_obj_set_grid_cell(obj, LV_GRID_ALIGN_STRETCH, 1, 2,
LV_GRID_ALIGN_STRETCH, 1, 1);
label = lv_label_create(obj);
lv_label_set_text(label, "c1-2, r1");
/*Cell to 0;1 but 2 rows tall (span = 2).Set width and height to stretched.*/
obj = lv_obj_create(cont);
lv_obj_set_size(obj, LV_SIZE_CONTENT, LV_SIZE_CONTENT);
lv_obj_set_grid_cell(obj, LV_GRID_ALIGN_STRETCH, 0, 1,
LV_GRID_ALIGN_STRETCH, 1, 2);
label = lv_label_create(obj);
lv_label_set_text(label, "c0\nr1-2");
}
#endif
Demonstrate grid's -free unit-
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_GRID && LV_BUILD_EXAMPLES
/**
* Demonstrate grid's "free unit"
*/
void lv_example_grid_3(void)
{
/*Column 1: fix width 60 px
*Column 2: 1 unit from the remaining free space
*Column 3: 2 unit from the remaining free space*/
static int32_t col_dsc[] = {60, LV_GRID_FR(1), LV_GRID_FR(2), LV_GRID_TEMPLATE_LAST};
/*Row 1: fix width 50 px
*Row 2: 1 unit from the remaining free space
*Row 3: fix width 50 px*/
static int32_t row_dsc[] = {50, LV_GRID_FR(1), 50, LV_GRID_TEMPLATE_LAST};
/*Create a container with grid*/
lv_obj_t * cont = lv_obj_create(lv_screen_active());
lv_obj_set_size(cont, 300, 220);
lv_obj_center(cont);
lv_obj_set_grid_dsc_array(cont, col_dsc, row_dsc);
lv_obj_t * label;
lv_obj_t * obj;
uint32_t i;
for(i = 0; i < 9; i++) {
uint8_t col = i % 3;
uint8_t row = i / 3;
obj = lv_obj_create(cont);
/*Stretch the cell horizontally and vertically too
*Set span to 1 to make the cell 1 column/row sized*/
lv_obj_set_grid_cell(obj, LV_GRID_ALIGN_STRETCH, col, 1,
LV_GRID_ALIGN_STRETCH, row, 1);
label = lv_label_create(obj);
lv_label_set_text_fmt(label, "%d,%d", col, row);
lv_obj_center(label);
}
}
#endif
Demonstrate track placement
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_GRID && LV_BUILD_EXAMPLES
/**
* Demonstrate track placement
*/
void lv_example_grid_4(void)
{
static int32_t col_dsc[] = {60, 60, 60, LV_GRID_TEMPLATE_LAST};
static int32_t row_dsc[] = {45, 45, 45, LV_GRID_TEMPLATE_LAST};
/*Add space between the columns and move the rows to the bottom (end)*/
/*Create a container with grid*/
lv_obj_t * cont = lv_obj_create(lv_screen_active());
lv_obj_set_grid_align(cont, LV_GRID_ALIGN_SPACE_BETWEEN, LV_GRID_ALIGN_END);
lv_obj_set_grid_dsc_array(cont, col_dsc, row_dsc);
lv_obj_set_size(cont, 300, 220);
lv_obj_center(cont);
lv_obj_t * label;
lv_obj_t * obj;
uint32_t i;
for(i = 0; i < 9; i++) {
uint8_t col = i % 3;
uint8_t row = i / 3;
obj = lv_obj_create(cont);
/*Stretch the cell horizontally and vertically too
*Set span to 1 to make the cell 1 column/row sized*/
lv_obj_set_grid_cell(obj, LV_GRID_ALIGN_STRETCH, col, 1,
LV_GRID_ALIGN_STRETCH, row, 1);
label = lv_label_create(obj);
lv_label_set_text_fmt(label, "%d,%d", col, row);
lv_obj_center(label);
}
}
#endif
Demonstrate column and row gap
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_GRID && LV_BUILD_EXAMPLES
static void row_gap_anim(void * obj, int32_t v)
{
lv_obj_set_style_pad_row(obj, v, 0);
}
static void column_gap_anim(void * obj, int32_t v)
{
lv_obj_set_style_pad_column(obj, v, 0);
}
/**
* Demonstrate column and row gap
*/
void lv_example_grid_5(void)
{
/*60x60 cells*/
static int32_t col_dsc[] = {60, 60, 60, LV_GRID_TEMPLATE_LAST};
static int32_t row_dsc[] = {45, 45, 45, LV_GRID_TEMPLATE_LAST};
/*Create a container with grid*/
lv_obj_t * cont = lv_obj_create(lv_screen_active());
lv_obj_set_size(cont, 300, 220);
lv_obj_center(cont);
lv_obj_set_grid_dsc_array(cont, col_dsc, row_dsc);
lv_obj_t * label;
lv_obj_t * obj;
uint32_t i;
for(i = 0; i < 9; i++) {
uint8_t col = i % 3;
uint8_t row = i / 3;
obj = lv_obj_create(cont);
lv_obj_set_grid_cell(obj, LV_GRID_ALIGN_STRETCH, col, 1,
LV_GRID_ALIGN_STRETCH, row, 1);
label = lv_label_create(obj);
lv_label_set_text_fmt(label, "%d,%d", col, row);
lv_obj_center(label);
}
lv_anim_t a;
lv_anim_init(&a);
lv_anim_set_var(&a, cont);
lv_anim_set_values(&a, 0, 10);
lv_anim_set_repeat_count(&a, LV_ANIM_REPEAT_INFINITE);
lv_anim_set_exec_cb(&a, row_gap_anim);
lv_anim_set_duration(&a, 500);
lv_anim_set_playback_duration(&a, 500);
lv_anim_start(&a);
lv_anim_set_exec_cb(&a, column_gap_anim);
lv_anim_set_duration(&a, 3000);
lv_anim_set_playback_duration(&a, 3000);
lv_anim_start(&a);
}
#endif
Demonstrate RTL direction on grid
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_GRID && LV_BUILD_EXAMPLES
/**
* Demonstrate RTL direction on grid
*/
void lv_example_grid_6(void)
{
static int32_t col_dsc[] = {60, 60, 60, LV_GRID_TEMPLATE_LAST};
static int32_t row_dsc[] = {45, 45, 45, LV_GRID_TEMPLATE_LAST};
/*Create a container with grid*/
lv_obj_t * cont = lv_obj_create(lv_screen_active());
lv_obj_set_size(cont, 300, 220);
lv_obj_center(cont);
lv_obj_set_style_base_dir(cont, LV_BASE_DIR_RTL, 0);
lv_obj_set_grid_dsc_array(cont, col_dsc, row_dsc);
lv_obj_t * label;
lv_obj_t * obj;
uint32_t i;
for(i = 0; i < 9; i++) {
uint8_t col = i % 3;
uint8_t row = i / 3;
obj = lv_obj_create(cont);
/*Stretch the cell horizontally and vertically too
*Set span to 1 to make the cell 1 column/row sized*/
lv_obj_set_grid_cell(obj, LV_GRID_ALIGN_STRETCH, col, 1,
LV_GRID_ALIGN_STRETCH, row, 1);
label = lv_label_create(obj);
lv_label_set_text_fmt(label, "%d,%d", col, row);
lv_obj_center(label);
}
}
#endif
Scrolling（滚动）
Nested scrolling
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES
static lv_obj_t * panel;
static lv_obj_t * save_button;
static lv_obj_t * restore_button;
static int saved_scroll_x;
static int saved_scroll_y;
static void scroll_update_cb(lv_event_t * e);
static void button_event_cb(lv_event_t * e);
static void scroll_update_cb(lv_event_t * e)
{
LV_UNUSED(e);
LV_LOG("scroll info: x:%3"LV_PRId32", y:%3"LV_PRId32", top:%3"LV_PRId32", "
"bottom:%3"LV_PRId32", left:%3"LV_PRId32", right:%3"LV_PRId32"\n",
lv_obj_get_scroll_x(panel),
lv_obj_get_scroll_y(panel),
lv_obj_get_scroll_top(panel),
lv_obj_get_scroll_bottom(panel),
lv_obj_get_scroll_left(panel),
lv_obj_get_scroll_right(panel)
);
}
static void button_event_cb(lv_event_t * e)
{
lv_obj_t * obj = lv_event_get_target_obj(e);
if(obj == save_button) {
saved_scroll_x = lv_obj_get_scroll_x(panel);
saved_scroll_y = lv_obj_get_scroll_y(panel);
}
else {
lv_obj_scroll_to(panel, saved_scroll_x, saved_scroll_y, LV_ANIM_ON);
}
}
/**
* Demonstrate how scrolling appears automatically
*/
void lv_example_scroll_1(void)
{
/*Create an object with the new style*/
lv_obj_t * scr;
scr = lv_screen_active();
panel = lv_obj_create(scr);
lv_obj_set_size(panel, 200, 200);
lv_obj_align(panel, LV_ALIGN_CENTER, 44, 0);
lv_obj_t * child;
lv_obj_t * label;
child = lv_obj_create(panel);
lv_obj_set_pos(child, 0, 0);
lv_obj_set_size(child, 70, 70);
label = lv_label_create(child);
lv_label_set_text(label, "Zero");
lv_obj_center(label);
child = lv_obj_create(panel);
lv_obj_set_pos(child, 160, 80);
lv_obj_set_size(child, 80, 80);
lv_obj_t * child2 = lv_button_create(child);
lv_obj_set_size(child2, 100, 50);
label = lv_label_create(child2);
lv_label_set_text(label, "Right");
lv_obj_center(label);
child = lv_obj_create(panel);
lv_obj_set_pos(child, 40, 160);
lv_obj_set_size(child, 100, 70);
label = lv_label_create(child);
lv_label_set_text(label, "Bottom");
lv_obj_center(label);
/* When LV_OBJ_FLAG_SCROLL_ELASTIC is cleared, scrolling does not go past edge bounaries. */
/* lv_obj_clear_flag(panel, LV_OBJ_FLAG_SCROLL_ELASTIC); */
/* Call `scroll_update_cb` while panel is being scrolled. */
lv_obj_add_event_cb(panel, scroll_update_cb, LV_EVENT_SCROLL, NULL);
/* Set up buttons that save and restore scroll position. */
save_button = lv_button_create(scr);
restore_button = lv_button_create(scr);
lv_obj_t * lbl;
lbl = lv_label_create(save_button);
lv_label_set_text_static(lbl, "Save");
lbl = lv_label_create(restore_button);
lv_label_set_text_static(lbl, "Restore");
lv_obj_align_to(save_button, panel, LV_ALIGN_OUT_LEFT_MID, -10, -20);
lv_obj_align_to(restore_button, panel, LV_ALIGN_OUT_LEFT_MID, -10, 20);
lv_obj_add_event_cb(save_button, button_event_cb, LV_EVENT_CLICKED, NULL);
lv_obj_add_event_cb(restore_button, button_event_cb, LV_EVENT_CLICKED, NULL);
}
#endif
Snapping
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_FLEX
static void sw_event_cb(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * sw = lv_event_get_target(e);
if(code == LV_EVENT_VALUE_CHANGED) {
lv_obj_t * list = lv_event_get_user_data(e);
if(lv_obj_has_state(sw, LV_STATE_CHECKED)) lv_obj_add_flag(list, LV_OBJ_FLAG_SCROLL_ONE);
else lv_obj_remove_flag(list, LV_OBJ_FLAG_SCROLL_ONE);
}
}
/**
* Show an example to scroll snap
*/
void lv_example_scroll_2(void)
{
lv_obj_t * panel = lv_obj_create(lv_screen_active());
lv_obj_set_size(panel, 280, 120);
lv_obj_set_scroll_snap_x(panel, LV_SCROLL_SNAP_CENTER);
lv_obj_set_flex_flow(panel, LV_FLEX_FLOW_ROW);
lv_obj_align(panel, LV_ALIGN_CENTER, 0, 20);
uint32_t i;
for(i = 0; i < 10; i++) {
lv_obj_t * btn = lv_button_create(panel);
lv_obj_set_size(btn, 150, lv_pct(100));
lv_obj_t * label = lv_label_create(btn);
if(i == 3) {
lv_label_set_text_fmt(label, "Panel %"LV_PRIu32"\nno snap", i);
lv_obj_remove_flag(btn, LV_OBJ_FLAG_SNAPPABLE);
}
else {
lv_label_set_text_fmt(label, "Panel %"LV_PRIu32, i);
}
lv_obj_center(label);
}
lv_obj_update_snap(panel, LV_ANIM_ON);
#if LV_USE_SWITCH
/*Switch between "One scroll" and "Normal scroll" mode*/
lv_obj_t * sw = lv_switch_create(lv_screen_active());
lv_obj_align(sw, LV_ALIGN_TOP_RIGHT, -20, 10);
lv_obj_add_event_cb(sw, sw_event_cb, LV_EVENT_ALL, panel);
lv_obj_t * label = lv_label_create(lv_screen_active());
lv_label_set_text(label, "One scroll");
lv_obj_align_to(label, sw, LV_ALIGN_OUT_BOTTOM_MID, 0, 5);
#endif
}
#endif
Styling the scrollbars
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_LIST
/**
* Styling the scrollbars
*/
void lv_example_scroll_4(void)
{
lv_obj_t * obj = lv_obj_create(lv_screen_active());
lv_obj_set_size(obj, 200, 100);
lv_obj_center(obj);
lv_obj_t * label = lv_label_create(obj);
lv_label_set_text(label,
"Lorem ipsum dolor sit amet, consectetur adipiscing elit.\n"
"Etiam dictum, tortor vestibulum lacinia laoreet, mi neque consectetur neque, vel mattis odio dolor egestas ligula. \n"
"Sed vestibulum sapien nulla, id convallis ex porttitor nec. \n"
"Duis et massa eu libero accumsan faucibus a in arcu. \n"
"Ut pulvinar odio lorem, vel tempus turpis condimentum quis. Nam consectetur condimentum sem in auctor. \n"
"Sed nisl augue, venenatis in blandit et, gravida ac tortor. \n"
"Etiam dapibus elementum suscipit. \n"
"Proin mollis sollicitudin convallis. \n"
"Integer dapibus tempus arcu nec viverra. \n"
"Donec molestie nulla enim, eu interdum velit placerat quis. \n"
"Donec id efficitur risus, at molestie turpis. \n"
"Suspendisse vestibulum consectetur nunc ut commodo. \n"
"Fusce molestie rhoncus nisi sit amet tincidunt. \n"
"Suspendisse a nunc ut magna ornare volutpat.");
/*Remove the style of scrollbar to have clean start*/
lv_obj_remove_style(obj, NULL, LV_PART_SCROLLBAR | LV_STATE_ANY);
/*Create a transition the animate the some properties on state change*/
static const lv_style_prop_t props[] = {LV_STYLE_BG_OPA, LV_STYLE_WIDTH, 0};
static lv_style_transition_dsc_t trans;
lv_style_transition_dsc_init(&trans, props, lv_anim_path_linear, 200, 0, NULL);
/*Create a style for the scrollbars*/
static lv_style_t style;
lv_style_init(&style);
lv_style_set_width(&style, 4); /*Width of the scrollbar*/
lv_style_set_pad_right(&style, 5); /*Space from the parallel side*/
lv_style_set_pad_top(&style, 5); /*Space from the perpendicular side*/
lv_style_set_radius(&style, 2);
lv_style_set_bg_opa(&style, LV_OPA_70);
lv_style_set_bg_color(&style, lv_palette_main(LV_PALETTE_BLUE));
lv_style_set_border_color(&style, lv_palette_darken(LV_PALETTE_BLUE, 3));
lv_style_set_border_width(&style, 2);
lv_style_set_shadow_width(&style, 8);
lv_style_set_shadow_spread(&style, 2);
lv_style_set_shadow_color(&style, lv_palette_darken(LV_PALETTE_BLUE, 1));
lv_style_set_transition(&style, &trans);
/*Make the scrollbars wider and use 100% opacity when scrolled*/
static lv_style_t style_scrolled;
lv_style_init(&style_scrolled);
lv_style_set_width(&style_scrolled, 8);
lv_style_set_bg_opa(&style_scrolled, LV_OPA_COVER);
lv_obj_add_style(obj, &style, LV_PART_SCROLLBAR);
lv_obj_add_style(obj, &style_scrolled, LV_PART_SCROLLBAR | LV_STATE_SCROLLED);
}
#endif
Right to left scrolling
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_FONT_DEJAVU_16_PERSIAN_HEBREW
/**
* Scrolling with Right To Left base direction
*/
void lv_example_scroll_5(void)
{
lv_obj_t * obj = lv_obj_create(lv_screen_active());
lv_obj_set_style_base_dir(obj, LV_BASE_DIR_RTL, 0);
lv_obj_set_size(obj, 200, 100);
lv_obj_center(obj);
lv_obj_t * label = lv_label_create(obj);
lv_label_set_text(label,
"میکروکُنترولر (به انگلیسی: Microcontroller) گونهای ریزپردازنده است که دارای حافظهٔ دسترسی تصادفی (RAM) و حافظهٔ فقطخواندنی (ROM)، تایمر، پورتهای ورودی و خروجی (I/O) و درگاه ترتیبی (Serial Port پورت سریال)، درون خود تراشه است، و میتواند به تنهایی ابزارهای دیگر را کنترل کند. به عبارت دیگر یک میکروکنترلر، مدار مجتمع کوچکی است که از یک CPU کوچک و اجزای دیگری مانند تایمر، درگاههای ورودی و خروجی آنالوگ و دیجیتال و حافظه تشکیل شدهاست.");
lv_obj_set_width(label, 400);
lv_obj_set_style_text_font(label, &lv_font_dejavu_16_persian_hebrew, 0);
}
#endif
Translate on scroll
C code
View on GitHub#include "../lv_examples.h"
#if LV_BUILD_EXAMPLES && LV_USE_FLEX
static void scroll_event_cb(lv_event_t * e)
{
lv_obj_t * cont = lv_event_get_target(e);
lv_area_t cont_a;
lv_obj_get_coords(cont, &cont_a);
int32_t cont_y_center = cont_a.y1 + lv_area_get_height(&cont_a) / 2;
int32_t r = lv_obj_get_height(cont) * 7 / 10;
uint32_t i;
uint32_t child_cnt = lv_obj_get_child_count(cont);
for(i = 0; i < child_cnt; i++) {
lv_obj_t * child = lv_obj_get_child(cont, i);
lv_area_t child_a;
lv_obj_get_coords(child, &child_a);
int32_t child_y_center = child_a.y1 + lv_area_get_height(&child_a) / 2;
int32_t diff_y = child_y_center - cont_y_center;
diff_y = LV_ABS(diff_y);
/*Get the x of diff_y on a circle.*/
int32_t x;
/*If diff_y is out of the circle use the last point of the circle (the radius)*/
if(diff_y >= r) {
x = r;
}
else {
/*Use Pythagoras theorem to get x from radius and y*/
uint32_t x_sqr = r * r - diff_y * diff_y;
lv_sqrt_res_t res;
lv_sqrt(x_sqr, &res, 0x8000); /*Use lvgl's built in sqrt root function*/
x = r - res.i;
}
/*Translate the item by the calculated X coordinate*/
lv_obj_set_style_translate_x(child, x, 0);
/*Use some opacity with larger translations*/
lv_opa_t opa = lv_map(x, 0, r, LV_OPA_TRANSP, LV_OPA_COVER);
lv_obj_set_style_opa(child, LV_OPA_COVER - opa, 0);
}
}
/**
* Translate the object as they scroll
*/
void lv_example_scroll_6(void)
{
lv_obj_t * cont = lv_obj_create(lv_screen_active());
lv_obj_set_size(cont, 200, 200);
lv_obj_center(cont);
lv_obj_set_flex_flow(cont, LV_FLEX_FLOW_COLUMN);
lv_obj_add_event_cb(cont, scroll_event_cb, LV_EVENT_SCROLL, NULL);
lv_obj_set_style_radius(cont, LV_RADIUS_CIRCLE, 0);
lv_obj_set_style_clip_corner(cont, true, 0);
lv_obj_set_scroll_dir(cont, LV_DIR_VER);
lv_obj_set_scroll_snap_y(cont, LV_SCROLL_SNAP_CENTER);
lv_obj_set_scrollbar_mode(cont, LV_SCROLLBAR_MODE_OFF);
uint32_t i;
for(i = 0; i < 20; i++) {
lv_obj_t * btn = lv_button_create(cont);
lv_obj_set_width(btn, lv_pct(100));
lv_obj_t * label = lv_label_create(btn);
lv_label_set_text_fmt(label, "Button %"LV_PRIu32, i);
}
/*Update the buttons position manually for first*/
lv_obj_send_event(cont, LV_EVENT_SCROLL, NULL);
/*Be sure the fist button is in the middle*/
lv_obj_scroll_to_view(lv_obj_get_child(cont, 0), LV_ANIM_OFF);
}
#endif
Widgets（控件）
Base object（基础对象）
Base objects with custom styles
C code
View on GitHub#include "../../lv_examples.h"
#if LV_BUILD_EXAMPLES
void lv_example_obj_1(void)
{
lv_obj_t * obj1;
obj1 = lv_obj_create(lv_screen_active());
lv_obj_set_size(obj1, 100, 50);
lv_obj_align(obj1, LV_ALIGN_CENTER, -60, -30);
static lv_style_t style_shadow;
lv_style_init(&style_shadow);
lv_style_set_shadow_width(&style_shadow, 10);
lv_style_set_shadow_spread(&style_shadow, 5);
lv_style_set_shadow_color(&style_shadow, lv_palette_main(LV_PALETTE_BLUE));
lv_obj_t * obj2;
obj2 = lv_obj_create(lv_screen_active());
lv_obj_add_style(obj2, &style_shadow, 0);
lv_obj_align(obj2, LV_ALIGN_CENTER, 60, 30);
}
#endif
Make an object draggable
C code
View on GitHub#include "../../lv_examples.h"
#if LV_BUILD_EXAMPLES
static void drag_event_handler(lv_event_t * e)
{
lv_obj_t * obj = lv_event_get_target(e);
lv_indev_t * indev = lv_indev_active();
if(indev == NULL) return;
lv_point_t vect;
lv_indev_get_vect(indev, &vect);
int32_t x = lv_obj_get_x_aligned(obj) + vect.x;
int32_t y = lv_obj_get_y_aligned(obj) + vect.y;
lv_obj_set_pos(obj, x, y);
}
/**
* Make an object draggable.
*/
void lv_example_obj_2(void)
{
lv_obj_t * obj;
obj = lv_obj_create(lv_screen_active());
lv_obj_set_size(obj, 150, 100);
lv_obj_add_event_cb(obj, drag_event_handler, LV_EVENT_PRESSING, NULL);
lv_obj_t * label = lv_label_create(obj);
lv_label_set_text(label, "Drag me");
lv_obj_center(label);
}
#endif
Transform object using a 3x3 matrix
C code
View on GitHub#include "../../lv_examples.h"
#if LV_BUILD_EXAMPLES
#if LV_DRAW_TRANSFORM_USE_MATRIX
static void timer_cb(lv_timer_t * timer)
{
lv_obj_t * obj = lv_timer_get_user_data(timer);
static float value = 0.1f;
lv_matrix_t matrix;
lv_matrix_identity(&matrix);
lv_matrix_scale(&matrix, value, 1);
lv_matrix_rotate(&matrix, value * 360);
lv_obj_set_transform(obj, &matrix);
value += 0.01f;
if(value > 2.0f) {
lv_obj_reset_transform(obj);
value = 0.1f;
}
}
void lv_example_obj_3(void)
{
lv_obj_t * obj = lv_obj_create(lv_screen_active());
lv_obj_center(obj);
lv_timer_create(timer_cb, 20, obj);
}
#else
void lv_example_obj_3(void)
{
lv_obj_t * label = lv_label_create(lv_screen_active());
lv_label_set_text_static(label, "LV_DRAW_TRANSFORM_USE_MATRIX is not enabled");
lv_obj_center(label);
}
#endif /*LV_DRAW_TRANSFORM_USE_MATRIX*/
#endif /*LV_BUILD_EXAMPLES*/
Arc（圆弧）
Simple Arc
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_ARC && LV_BUILD_EXAMPLES
static void value_changed_event_cb(lv_event_t * e);
void lv_example_arc_1(void)
{
lv_obj_t * label = lv_label_create(lv_screen_active());
/*Create an Arc*/
lv_obj_t * arc = lv_arc_create(lv_screen_active());
lv_obj_set_size(arc, 150, 150);
lv_arc_set_rotation(arc, 135);
lv_arc_set_bg_angles(arc, 0, 270);
lv_arc_set_value(arc, 10);
lv_obj_center(arc);
lv_obj_add_event_cb(arc, value_changed_event_cb, LV_EVENT_VALUE_CHANGED, label);
/*Manually update the label for the first time*/
lv_obj_send_event(arc, LV_EVENT_VALUE_CHANGED, NULL);
}
static void value_changed_event_cb(lv_event_t * e)
{
lv_obj_t * arc = lv_event_get_target(e);
lv_obj_t * label = lv_event_get_user_data(e);
lv_label_set_text_fmt(label, "%" LV_PRId32 "%%", lv_arc_get_value(arc));
/*Rotate the label to the current position of the arc*/
lv_arc_rotate_obj_to_angle(arc, label, 25);
}
#endif
Loader with Arc
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_ARC && LV_BUILD_EXAMPLES
static void set_angle(void * obj, int32_t v)
{
lv_arc_set_value(obj, v);
}
/**
* Create an arc which acts as a loader.
*/
void lv_example_arc_2(void)
{
/*Create an Arc*/
lv_obj_t * arc = lv_arc_create(lv_screen_active());
lv_arc_set_rotation(arc, 270);
lv_arc_set_bg_angles(arc, 0, 360);
lv_obj_remove_style(arc, NULL, LV_PART_KNOB); /*Be sure the knob is not displayed*/
lv_obj_remove_flag(arc, LV_OBJ_FLAG_CLICKABLE); /*To not allow adjusting by click*/
lv_obj_center(arc);
lv_anim_t a;
lv_anim_init(&a);
lv_anim_set_var(&a, arc);
lv_anim_set_exec_cb(&a, set_angle);
lv_anim_set_duration(&a, 1000);
lv_anim_set_repeat_count(&a, LV_ANIM_REPEAT_INFINITE); /*Just for the demo*/
lv_anim_set_repeat_delay(&a, 500);
lv_anim_set_values(&a, 0, 100);
lv_anim_start(&a);
}
#endif
Bar（进度条）
Simple Bar
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_BAR && LV_BUILD_EXAMPLES
void lv_example_bar_1(void)
{
lv_obj_t * bar1 = lv_bar_create(lv_screen_active());
lv_obj_set_size(bar1, 200, 20);
lv_obj_center(bar1);
lv_bar_set_value(bar1, 70, LV_ANIM_OFF);
}
#endif
Styling a bar
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_BAR && LV_BUILD_EXAMPLES
/**
* Example of styling the bar
*/
void lv_example_bar_2(void)
{
static lv_style_t style_bg;
static lv_style_t style_indic;
lv_style_init(&style_bg);
lv_style_set_border_color(&style_bg, lv_palette_main(LV_PALETTE_BLUE));
lv_style_set_border_width(&style_bg, 2);
lv_style_set_pad_all(&style_bg, 6); /*To make the indicator smaller*/
lv_style_set_radius(&style_bg, 6);
lv_style_set_anim_duration(&style_bg, 1000);
lv_style_init(&style_indic);
lv_style_set_bg_opa(&style_indic, LV_OPA_COVER);
lv_style_set_bg_color(&style_indic, lv_palette_main(LV_PALETTE_BLUE));
lv_style_set_radius(&style_indic, 3);
lv_obj_t * bar = lv_bar_create(lv_screen_active());
lv_obj_remove_style_all(bar); /*To have a clean start*/
lv_obj_add_style(bar, &style_bg, 0);
lv_obj_add_style(bar, &style_indic, LV_PART_INDICATOR);
lv_obj_set_size(bar, 200, 20);
lv_obj_center(bar);
lv_bar_set_value(bar, 100, LV_ANIM_ON);
}
#endif
Temperature meter
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_BAR && LV_BUILD_EXAMPLES
static void set_temp(void * bar, int32_t temp)
{
lv_bar_set_value(bar, temp, LV_ANIM_ON);
}
/**
* A temperature meter example
*/
void lv_example_bar_3(void)
{
static lv_style_t style_indic;
lv_style_init(&style_indic);
lv_style_set_bg_opa(&style_indic, LV_OPA_COVER);
lv_style_set_bg_color(&style_indic, lv_palette_main(LV_PALETTE_RED));
lv_style_set_bg_grad_color(&style_indic, lv_palette_main(LV_PALETTE_BLUE));
lv_style_set_bg_grad_dir(&style_indic, LV_GRAD_DIR_VER);
lv_obj_t * bar = lv_bar_create(lv_screen_active());
lv_obj_add_style(bar, &style_indic, LV_PART_INDICATOR);
lv_obj_set_size(bar, 20, 200);
lv_obj_center(bar);
lv_bar_set_range(bar, -20, 40);
lv_anim_t a;
lv_anim_init(&a);
lv_anim_set_exec_cb(&a, set_temp);
lv_anim_set_duration(&a, 3000);
lv_anim_set_playback_duration(&a, 3000);
lv_anim_set_var(&a, bar);
lv_anim_set_values(&a, -20, 40);
lv_anim_set_repeat_count(&a, LV_ANIM_REPEAT_INFINITE);
lv_anim_start(&a);
}
#endif
Stripe pattern and range value
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_BAR && LV_BUILD_EXAMPLES
/**
* Bar with stripe pattern and ranged value
*/
void lv_example_bar_4(void)
{
LV_IMAGE_DECLARE(img_skew_strip);
static lv_style_t style_indic;
lv_style_init(&style_indic);
lv_style_set_bg_image_src(&style_indic, &img_skew_strip);
lv_style_set_bg_image_tiled(&style_indic, true);
lv_style_set_bg_image_opa(&style_indic, LV_OPA_30);
lv_obj_t * bar = lv_bar_create(lv_screen_active());
lv_obj_add_style(bar, &style_indic, LV_PART_INDICATOR);
lv_obj_set_size(bar, 260, 20);
lv_obj_center(bar);
lv_bar_set_mode(bar, LV_BAR_MODE_RANGE);
lv_bar_set_value(bar, 90, LV_ANIM_OFF);
lv_bar_set_start_value(bar, 20, LV_ANIM_OFF);
}
#endif
Bar with LTR and RTL base direction
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_BAR && LV_BUILD_EXAMPLES
/**
* Bar with LTR and RTL base direction
*/
void lv_example_bar_5(void)
{
lv_obj_t * label;
lv_obj_t * bar_ltr = lv_bar_create(lv_screen_active());
lv_obj_set_size(bar_ltr, 200, 20);
lv_bar_set_value(bar_ltr, 70, LV_ANIM_OFF);
lv_obj_align(bar_ltr, LV_ALIGN_CENTER, 0, -30);
label = lv_label_create(lv_screen_active());
lv_label_set_text(label, "Left to Right base direction");
lv_obj_align_to(label, bar_ltr, LV_ALIGN_OUT_TOP_MID, 0, -5);
lv_obj_t * bar_rtl = lv_bar_create(lv_screen_active());
lv_obj_set_style_base_dir(bar_rtl, LV_BASE_DIR_RTL, 0);
lv_obj_set_size(bar_rtl, 200, 20);
lv_bar_set_value(bar_rtl, 70, LV_ANIM_OFF);
lv_obj_align(bar_rtl, LV_ALIGN_CENTER, 0, 30);
label = lv_label_create(lv_screen_active());
lv_label_set_text(label, "Right to Left base direction");
lv_obj_align_to(label, bar_rtl, LV_ALIGN_OUT_TOP_MID, 0, -5);
}
#endif
Custom drawer to show the current value
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_BAR && LV_BUILD_EXAMPLES
#define MAX_VALUE 100
#define MIN_VALUE 0
static void set_value(void * bar, int32_t v)
{
lv_bar_set_value(bar, v, LV_ANIM_OFF);
}
static void event_cb(lv_event_t * e)
{
lv_obj_t * obj = lv_event_get_target(e);
lv_draw_label_dsc_t label_dsc;
lv_draw_label_dsc_init(&label_dsc);
label_dsc.font = LV_FONT_DEFAULT;
char buf[8];
lv_snprintf(buf, sizeof(buf), "%d", (int)lv_bar_get_value(obj));
lv_point_t txt_size;
lv_text_get_size(&txt_size, buf, label_dsc.font, label_dsc.letter_space, label_dsc.line_space, LV_COORD_MAX,
label_dsc.flag);
lv_area_t txt_area;
txt_area.x1 = 0;
txt_area.x2 = txt_size.x - 1;
txt_area.y1 = 0;
txt_area.y2 = txt_size.y - 1;
lv_area_t indic_area;
lv_obj_get_coords(obj, &indic_area);
lv_area_set_width(&indic_area, lv_area_get_width(&indic_area) * lv_bar_get_value(obj) / MAX_VALUE);
/*If the indicator is long enough put the text inside on the right*/
if(lv_area_get_width(&indic_area) > txt_size.x + 20) {
lv_area_align(&indic_area, &txt_area, LV_ALIGN_RIGHT_MID, -10, 0);
label_dsc.color = lv_color_white();
}
/*If the indicator is still short put the text out of it on the right*/
else {
lv_area_align(&indic_area, &txt_area, LV_ALIGN_OUT_RIGHT_MID, 10, 0);
label_dsc.color = lv_color_black();
}
label_dsc.text = buf;
label_dsc.text_local = true;
lv_layer_t * layer = lv_event_get_layer(e);
lv_draw_label(layer, &label_dsc, &txt_area);
}
/**
* Custom drawer on the bar to display the current value
*/
void lv_example_bar_6(void)
{
lv_obj_t * bar = lv_bar_create(lv_screen_active());
lv_bar_set_range(bar, MIN_VALUE, MAX_VALUE);
lv_obj_set_size(bar, 200, 20);
lv_obj_center(bar);
lv_obj_add_event_cb(bar, event_cb, LV_EVENT_DRAW_MAIN_END, NULL);
lv_anim_t a;
lv_anim_init(&a);
lv_anim_set_var(&a, bar);
lv_anim_set_values(&a, 0, 100);
lv_anim_set_exec_cb(&a, set_value);
lv_anim_set_duration(&a, 4000);
lv_anim_set_playback_duration(&a, 4000);
lv_anim_set_repeat_count(&a, LV_ANIM_REPEAT_INFINITE);
lv_anim_start(&a);
}
#endif
Bar with opposite direction
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_BAR && LV_BUILD_EXAMPLES
/**
* Bar with opposite direction
*/
void lv_example_bar_7(void)
{
lv_obj_t * label;
lv_obj_t * bar_tob = lv_bar_create(lv_screen_active());
lv_obj_set_size(bar_tob, 20, 200);
lv_bar_set_range(bar_tob, 100, 0);
lv_bar_set_value(bar_tob, 70, LV_ANIM_OFF);
lv_obj_align(bar_tob, LV_ALIGN_CENTER, 0, -30);
label = lv_label_create(lv_screen_active());
lv_label_set_text(label, "From top to bottom");
lv_obj_align_to(label, bar_tob, LV_ALIGN_OUT_TOP_MID, 0, -5);
}
#endif
Calendar（日历）
Calendar with header
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_CALENDAR && LV_BUILD_EXAMPLES
static void event_handler(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * obj = lv_event_get_current_target(e);
if(code == LV_EVENT_VALUE_CHANGED) {
lv_calendar_date_t date;
if(lv_calendar_get_pressed_date(obj, &date)) {
LV_LOG_USER("Clicked date: %02d.%02d.%d", date.day, date.month, date.year);
}
}
}
void lv_example_calendar_1(void)
{
lv_obj_t * calendar = lv_calendar_create(lv_screen_active());
lv_obj_set_size(calendar, 185, 230);
lv_obj_align(calendar, LV_ALIGN_CENTER, 0, 27);
lv_obj_add_event_cb(calendar, event_handler, LV_EVENT_ALL, NULL);
lv_calendar_set_today_date(calendar, 2021, 02, 23);
lv_calendar_set_showed_date(calendar, 2021, 02);
/*Highlight a few days*/
static lv_calendar_date_t highlighted_days[3]; /*Only its pointer will be saved so should be static*/
highlighted_days[0].year = 2021;
highlighted_days[0].month = 02;
highlighted_days[0].day = 6;
highlighted_days[1].year = 2021;
highlighted_days[1].month = 02;
highlighted_days[1].day = 11;
highlighted_days[2].year = 2022;
highlighted_days[2].month = 02;
highlighted_days[2].day = 22;
lv_calendar_set_highlighted_dates(calendar, highlighted_days, 3);
#if LV_USE_CALENDAR_HEADER_DROPDOWN
lv_calendar_header_dropdown_create(calendar);
#elif LV_USE_CALENDAR_HEADER_ARROW
lv_calendar_header_arrow_create(calendar);
#endif
}
#endif
Chinese calendar
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_CALENDAR && LV_USE_CALENDAR_CHINESE && LV_BUILD_EXAMPLES
void lv_example_calendar_2(void)
{
lv_obj_t * calendar = lv_calendar_create(lv_screen_active());
lv_obj_set_size(calendar, 300, 300);
lv_obj_align(calendar, LV_ALIGN_TOP_MID, 0, 0);
lv_calendar_set_today_date(calendar, 2024, 03, 22);
lv_calendar_set_showed_date(calendar, 2024, 03);
#if LV_USE_CALENDAR_HEADER_DROPDOWN
lv_calendar_header_dropdown_create(calendar);
#elif LV_USE_CALENDAR_HEADER_ARROW
lv_calendar_header_arrow_create(calendar);
#endif
lv_calendar_set_chinese_mode(calendar, true);
lv_obj_set_style_text_font(calendar, &lv_font_simsun_14_cjk, LV_PART_MAIN);
}
#else
void lv_example_calendar_2(void)
{
lv_obj_t * label = lv_label_create(lv_screen_active());
lv_label_set_text(label, "chinese calendar is not enabled");
lv_obj_center(label);
}
#endif
Canvas（画布）
Drawing on the Canvas and rotate
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_CANVAS && LV_BUILD_EXAMPLES
#define CANVAS_WIDTH 200
#define CANVAS_HEIGHT 150
void lv_example_canvas_1(void)
{
lv_draw_rect_dsc_t rect_dsc;
lv_draw_rect_dsc_init(&rect_dsc);
rect_dsc.radius = 10;
rect_dsc.bg_opa = LV_OPA_COVER;
rect_dsc.bg_grad.dir = LV_GRAD_DIR_VER;
rect_dsc.bg_grad.stops[0].color = lv_palette_main(LV_PALETTE_RED);
rect_dsc.bg_grad.stops[0].opa = LV_OPA_100;
rect_dsc.bg_grad.stops[1].color = lv_palette_main(LV_PALETTE_BLUE);
rect_dsc.bg_grad.stops[1].opa = LV_OPA_50;
rect_dsc.border_width = 2;
rect_dsc.border_opa = LV_OPA_90;
rect_dsc.border_color = lv_color_white();
rect_dsc.shadow_width = 5;
rect_dsc.shadow_offset_x = 5;
rect_dsc.shadow_offset_y = 5;
lv_draw_label_dsc_t label_dsc;
lv_draw_label_dsc_init(&label_dsc);
label_dsc.color = lv_palette_main(LV_PALETTE_ORANGE);
label_dsc.text = "Some text on text canvas";
/*Create a buffer for the canvas*/
LV_DRAW_BUF_DEFINE_STATIC(draw_buf_16bpp, CANVAS_WIDTH, CANVAS_HEIGHT, LV_COLOR_FORMAT_RGB565);
LV_DRAW_BUF_INIT_STATIC(draw_buf_16bpp);
lv_obj_t * canvas = lv_canvas_create(lv_screen_active());
lv_canvas_set_draw_buf(canvas, &draw_buf_16bpp);
lv_obj_center(canvas);
lv_canvas_fill_bg(canvas, lv_palette_lighten(LV_PALETTE_GREY, 3), LV_OPA_COVER);
lv_layer_t layer;
lv_canvas_init_layer(canvas, &layer);
lv_area_t coords_rect = {30, 20, 100, 70};
lv_draw_rect(&layer, &rect_dsc, &coords_rect);
lv_area_t coords_text = {40, 80, 100, 120};
lv_draw_label(&layer, &label_dsc, &coords_text);
lv_canvas_finish_layer(canvas, &layer);
/*Test the rotation. It requires another buffer where the original image is stored.
*So use previous canvas as image and rotate it to the new canvas*/
LV_DRAW_BUF_DEFINE_STATIC(draw_buf_32bpp, CANVAS_WIDTH, CANVAS_HEIGHT, LV_COLOR_FORMAT_ARGB8888);
LV_DRAW_BUF_INIT_STATIC(draw_buf_32bpp);
/*Create a canvas and initialize its palette*/
canvas = lv_canvas_create(lv_screen_active());
lv_canvas_set_draw_buf(canvas, &draw_buf_32bpp);
lv_canvas_fill_bg(canvas, lv_color_hex3(0xccc), LV_OPA_COVER);
lv_obj_center(canvas);
lv_canvas_fill_bg(canvas, lv_palette_lighten(LV_PALETTE_GREY, 1), LV_OPA_COVER);
lv_canvas_init_layer(canvas, &layer);
lv_image_dsc_t img;
lv_draw_buf_to_image(&draw_buf_16bpp, &img);
lv_draw_image_dsc_t img_dsc;
lv_draw_image_dsc_init(&img_dsc);
img_dsc.rotation = 120;
img_dsc.src = &img;
img_dsc.pivot.x = CANVAS_WIDTH / 2;
img_dsc.pivot.y = CANVAS_HEIGHT / 2;
lv_area_t coords_img = {0, 0, CANVAS_WIDTH - 1, CANVAS_HEIGHT - 1};
lv_draw_image(&layer, &img_dsc, &coords_img);
lv_canvas_finish_layer(canvas, &layer);
}
#endif
Transparent Canvas with chroma keying
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_CANVAS && LV_BUILD_EXAMPLES
#define CANVAS_WIDTH 80
#define CANVAS_HEIGHT 40
/**
* Create a transparent canvas with transparency
*/
void lv_example_canvas_2(void)
{
lv_obj_set_style_bg_color(lv_screen_active(), lv_palette_lighten(LV_PALETTE_RED, 5), 0);
/*Create a buffer for the canvas*/
LV_DRAW_BUF_DEFINE_STATIC(draw_buf, CANVAS_WIDTH, CANVAS_HEIGHT, LV_COLOR_FORMAT_ARGB8888);
LV_DRAW_BUF_INIT_STATIC(draw_buf);
/*Create a canvas and initialize its palette*/
lv_obj_t * canvas = lv_canvas_create(lv_screen_active());
lv_canvas_set_draw_buf(canvas, &draw_buf);
lv_obj_center(canvas);
/*Red background (There is no dedicated alpha channel in indexed images so LV_OPA_COVER is ignored)*/
lv_canvas_fill_bg(canvas, lv_palette_main(LV_PALETTE_BLUE), LV_OPA_COVER);
/*Create hole on the canvas*/
uint32_t x;
uint32_t y;
for(y = 10; y < 20; y++) {
for(x = 5; x < 75; x++) {
lv_canvas_set_px(canvas, x, y, lv_palette_main(LV_PALETTE_BLUE), LV_OPA_50);
}
}
for(y = 20; y < 30; y++) {
for(x = 5; x < 75; x++) {
lv_canvas_set_px(canvas, x, y, lv_palette_main(LV_PALETTE_BLUE), LV_OPA_20);
}
}
for(y = 30; y < 40; y++) {
for(x = 5; x < 75; x++) {
lv_canvas_set_px(canvas, x, y, lv_palette_main(LV_PALETTE_BLUE), LV_OPA_0);
}
}
}
#endif
Draw a rectangle to the canvas
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_CANVAS && LV_BUILD_EXAMPLES
#define CANVAS_WIDTH 50
#define CANVAS_HEIGHT 50
/**
* Draw a rectangle to the canvas
*/
void lv_example_canvas_3(void)
{
/*Create a buffer for the canvas*/
LV_DRAW_BUF_DEFINE_STATIC(draw_buf, CANVAS_WIDTH, CANVAS_HEIGHT, LV_COLOR_FORMAT_ARGB8888);
LV_DRAW_BUF_INIT_STATIC(draw_buf);
/*Create a canvas and initialize its palette*/
lv_obj_t * canvas = lv_canvas_create(lv_screen_active());
lv_canvas_set_draw_buf(canvas, &draw_buf);
lv_canvas_fill_bg(canvas, lv_color_hex3(0xccc), LV_OPA_COVER);
lv_obj_center(canvas);
lv_layer_t layer;
lv_canvas_init_layer(canvas, &layer);
lv_draw_rect_dsc_t dsc;
lv_draw_rect_dsc_init(&dsc);
dsc.bg_color = lv_palette_main(LV_PALETTE_RED);
dsc.border_color = lv_palette_main(LV_PALETTE_BLUE);
dsc.border_width = 3;
dsc.outline_color = lv_palette_main(LV_PALETTE_GREEN);
dsc.outline_width = 2;
dsc.outline_pad = 2;
dsc.outline_opa = LV_OPA_50;
dsc.radius = 5;
dsc.border_width = 3;
lv_area_t coords = {10, 10, 40, 30};
lv_draw_rect(&layer, &dsc, &coords);
lv_canvas_finish_layer(canvas, &layer);
}
#endif
Draw a label to the canvas
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_CANVAS && LV_FONT_MONTSERRAT_18 && LV_BUILD_EXAMPLES
#define CANVAS_WIDTH 50
#define CANVAS_HEIGHT 50
/**
* Draw a text to the canvas
*/
void lv_example_canvas_4(void)
{
/*Create a buffer for the canvas*/
LV_DRAW_BUF_DEFINE_STATIC(draw_buf, CANVAS_WIDTH, CANVAS_HEIGHT, LV_COLOR_FORMAT_ARGB8888);
LV_DRAW_BUF_INIT_STATIC(draw_buf);
/*Create a canvas and initialize its palette*/
lv_obj_t * canvas = lv_canvas_create(lv_screen_active());
lv_canvas_set_draw_buf(canvas, &draw_buf);
lv_canvas_fill_bg(canvas, lv_color_hex3(0xccc), LV_OPA_COVER);
lv_obj_center(canvas);
lv_layer_t layer;
lv_canvas_init_layer(canvas, &layer);
lv_draw_label_dsc_t dsc;
lv_draw_label_dsc_init(&dsc);
dsc.color = lv_palette_main(LV_PALETTE_RED);
dsc.font = &lv_font_montserrat_18;
dsc.decor = LV_TEXT_DECOR_UNDERLINE;
dsc.text = "Hello";
lv_area_t coords = {10, 10, 30, 60};
lv_draw_label(&layer, &dsc, &coords);
lv_canvas_finish_layer(canvas, &layer);
}
#endif
Draw an arc to the canvas
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_CANVAS && LV_BUILD_EXAMPLES
#define CANVAS_WIDTH 50
#define CANVAS_HEIGHT 50
/**
* Draw an arc to the canvas
*/
void lv_example_canvas_5(void)
{
/*Create a buffer for the canvas*/
LV_DRAW_BUF_DEFINE_STATIC(draw_buf, CANVAS_WIDTH, CANVAS_HEIGHT, LV_COLOR_FORMAT_ARGB8888);
LV_DRAW_BUF_INIT_STATIC(draw_buf);
/*Create a canvas and initialize its palette*/
lv_obj_t * canvas = lv_canvas_create(lv_screen_active());
lv_canvas_set_draw_buf(canvas, &draw_buf);
lv_canvas_fill_bg(canvas, lv_color_hex3(0xccc), LV_OPA_COVER);
lv_obj_center(canvas);
lv_layer_t layer;
lv_canvas_init_layer(canvas, &layer);
lv_draw_arc_dsc_t dsc;
lv_draw_arc_dsc_init(&dsc);
dsc.color = lv_palette_main(LV_PALETTE_RED);
dsc.width = 5;
dsc.center.x = 25;
dsc.center.y = 25;
dsc.width = 10;
dsc.radius = 15;
dsc.start_angle = 0;
dsc.end_angle = 220;
lv_draw_arc(&layer, &dsc);
lv_canvas_finish_layer(canvas, &layer);
}
#endif
Draw an image to the canvas
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_CANVAS && LV_BUILD_EXAMPLES
#define CANVAS_WIDTH 50
#define CANVAS_HEIGHT 50
/**
* Draw an image to the canvas
*/
void lv_example_canvas_6(void)
{
/*Create a buffer for the canvas*/
static uint8_t cbuf[LV_CANVAS_BUF_SIZE(CANVAS_WIDTH, CANVAS_HEIGHT, 32, LV_DRAW_BUF_STRIDE_ALIGN)];
/*Create a canvas and initialize its palette*/
lv_obj_t * canvas = lv_canvas_create(lv_screen_active());
lv_canvas_set_buffer(canvas, cbuf, CANVAS_WIDTH, CANVAS_HEIGHT, LV_COLOR_FORMAT_ARGB8888);
lv_canvas_fill_bg(canvas, lv_color_hex3(0xccc), LV_OPA_COVER);
lv_obj_center(canvas);
lv_layer_t layer;
lv_canvas_init_layer(canvas, &layer);
LV_IMAGE_DECLARE(img_star);
lv_draw_image_dsc_t dsc;
lv_draw_image_dsc_init(&dsc);
dsc.src = &img_star;
lv_area_t coords = {10, 10, 10 + img_star.header.w - 1, 10 + img_star.header.h - 1};
lv_draw_image(&layer, &dsc, &coords);
lv_canvas_finish_layer(canvas, &layer);
}
#endif
Draw a line to the canvas
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_CANVAS&& LV_BUILD_EXAMPLES
#define CANVAS_WIDTH 50
#define CANVAS_HEIGHT 50
/**
* Draw a line to the canvas
*/
void lv_example_canvas_7(void)
{
/*Create a buffer for the canvas*/
LV_DRAW_BUF_DEFINE_STATIC(draw_buf, CANVAS_WIDTH, CANVAS_HEIGHT, LV_COLOR_FORMAT_ARGB8888);
LV_DRAW_BUF_INIT_STATIC(draw_buf);
/*Create a canvas and initialize its palette*/
lv_obj_t * canvas = lv_canvas_create(lv_screen_active());
lv_canvas_set_draw_buf(canvas, &draw_buf);
lv_canvas_fill_bg(canvas, lv_color_hex3(0xccc), LV_OPA_COVER);
lv_obj_center(canvas);
lv_layer_t layer;
lv_canvas_init_layer(canvas, &layer);
lv_draw_line_dsc_t dsc;
lv_draw_line_dsc_init(&dsc);
dsc.color = lv_palette_main(LV_PALETTE_RED);
dsc.width = 4;
dsc.round_end = 1;
dsc.round_start = 1;
dsc.p1.x = 15;
dsc.p1.y = 15;
dsc.p2.x = 35;
dsc.p2.y = 10;
lv_draw_line(&layer, &dsc);
lv_canvas_finish_layer(canvas, &layer);
}
#endif
Draw a vector graphic to the canvas
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_CANVAS && LV_BUILD_EXAMPLES
#if LV_USE_VECTOR_GRAPHIC
#define CANVAS_WIDTH 150
#define CANVAS_HEIGHT 150
/**
* Draw a path to the canvas
*/
void lv_example_canvas_8(void)
{
/*Create a buffer for the canvas*/
LV_DRAW_BUF_DEFINE_STATIC(draw_buf, CANVAS_WIDTH, CANVAS_HEIGHT, LV_COLOR_FORMAT_ARGB8888);
LV_DRAW_BUF_INIT_STATIC(draw_buf);
/*Create a canvas and initialize its palette*/
lv_obj_t * canvas = lv_canvas_create(lv_screen_active());
lv_canvas_set_draw_buf(canvas, &draw_buf);
lv_canvas_fill_bg(canvas, lv_color_hex3(0xccc), LV_OPA_COVER);
lv_obj_center(canvas);
lv_layer_t layer;
lv_canvas_init_layer(canvas, &layer);
lv_vector_dsc_t * dsc = lv_vector_dsc_create(&layer);
lv_vector_path_t * path = lv_vector_path_create(LV_VECTOR_PATH_QUALITY_MEDIUM);
lv_fpoint_t pts[] = {{10, 10}, {130, 130}, {10, 130}};
lv_vector_path_move_to(path, &pts[0]);
lv_vector_path_line_to(path, &pts[1]);
lv_vector_path_line_to(path, &pts[2]);
lv_vector_path_close(path);
lv_vector_dsc_set_fill_color(dsc, lv_color_make(0x00, 0x80, 0xff));
lv_vector_dsc_add_path(dsc, path);
lv_draw_vector(dsc);
lv_vector_path_delete(path);
lv_vector_dsc_delete(dsc);
lv_canvas_finish_layer(canvas, &layer);
}
#else
void lv_example_canvas_8(void)
{
/*fallback for online examples*/
lv_obj_t * label = lv_label_create(lv_screen_active());
lv_label_set_text(label, "Vector graphics is not enabled");
lv_obj_center(label);
}
#endif /*LV_USE_VECTOR_GRAPHIC*/
#endif
Chart（图表）
Line Chart
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_CHART && LV_BUILD_EXAMPLES
/**
* A very basic line chart
*/
void lv_example_chart_1(void)
{
/*Create a chart*/
lv_obj_t * chart;
chart = lv_chart_create(lv_screen_active());
lv_obj_set_size(chart, 200, 150);
lv_obj_center(chart);
lv_chart_set_type(chart, LV_CHART_TYPE_LINE); /*Show lines and points too*/
/*Add two data series*/
lv_chart_series_t * ser1 = lv_chart_add_series(chart, lv_palette_main(LV_PALETTE_GREEN), LV_CHART_AXIS_PRIMARY_Y);
lv_chart_series_t * ser2 = lv_chart_add_series(chart, lv_palette_main(LV_PALETTE_RED), LV_CHART_AXIS_SECONDARY_Y);
int32_t * ser2_y_points = lv_chart_get_y_array(chart, ser2);
uint32_t i;
for(i = 0; i < 10; i++) {
/*Set the next points on 'ser1'*/
lv_chart_set_next_value(chart, ser1, lv_rand(10, 50));
/*Directly set points on 'ser2'*/
ser2_y_points[i] = lv_rand(50, 90);
}
lv_chart_refresh(chart); /*Required after direct set*/
}
#endif
Axis ticks and labels with scrolling
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_CHART && LV_BUILD_EXAMPLES
/**
* Use lv_scale to add ticks to a scrollable chart
*/
void lv_example_chart_2(void)
{
/*Create a container*/
lv_obj_t * main_cont = lv_obj_create(lv_screen_active());
lv_obj_set_size(main_cont, 200, 150);
lv_obj_center(main_cont);
/*Create a transparent wrapper for the chart and the scale.
*Set a large width, to make it scrollable on the main container*/
lv_obj_t * wrapper = lv_obj_create(main_cont);
lv_obj_remove_style_all(wrapper);
lv_obj_set_size(wrapper, lv_pct(300), lv_pct(100));
lv_obj_set_flex_flow(wrapper, LV_FLEX_FLOW_COLUMN);
/*Create a chart on the wrapper
*Set it's width to 100% to fill the large wrapper*/
lv_obj_t * chart = lv_chart_create(wrapper);
lv_obj_set_width(chart, lv_pct(100));
lv_obj_set_flex_grow(chart, 1);
lv_chart_set_type(chart, LV_CHART_TYPE_BAR);
lv_chart_set_range(chart, LV_CHART_AXIS_PRIMARY_Y, 0, 100);
lv_chart_set_range(chart, LV_CHART_AXIS_SECONDARY_Y, 0, 400);
lv_chart_set_point_count(chart, 12);
lv_obj_set_style_radius(chart, 0, 0);
/*Create a scale also with 100% width*/
lv_obj_t * scale_bottom = lv_scale_create(wrapper);
lv_scale_set_mode(scale_bottom, LV_SCALE_MODE_HORIZONTAL_BOTTOM);
lv_obj_set_size(scale_bottom, lv_pct(100), 25);
lv_scale_set_total_tick_count(scale_bottom, 12);
lv_scale_set_major_tick_every(scale_bottom, 1);
lv_obj_set_style_pad_hor(scale_bottom, lv_chart_get_first_point_center_offset(chart), 0);
static const char * month[] = {"Jan", "Febr", "March", "Apr", "May", "Jun", "July", "Aug", "Sept", "Oct", "Nov", "Dec", NULL};
lv_scale_set_text_src(scale_bottom, month);
/*Add two data series*/
lv_chart_series_t * ser1 = lv_chart_add_series(chart, lv_palette_lighten(LV_PALETTE_GREEN, 2), LV_CHART_AXIS_PRIMARY_Y);
lv_chart_series_t * ser2 = lv_chart_add_series(chart, lv_palette_darken(LV_PALETTE_GREEN, 2), LV_CHART_AXIS_PRIMARY_Y);
/*Set the next points on 'ser1'*/
uint32_t i;
for(i = 0; i < 12; i++) {
lv_chart_set_next_value(chart, ser1, lv_rand(10, 60));
lv_chart_set_next_value(chart, ser2, lv_rand(50, 90));
}
lv_chart_refresh(chart); /*Required after direct set*/
}
#endif
Show the value of the pressed points
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_CHART && LV_BUILD_EXAMPLES
static void event_cb(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * chart = lv_event_get_target(e);
if(code == LV_EVENT_VALUE_CHANGED) {
lv_obj_invalidate(chart);
}
if(code == LV_EVENT_REFR_EXT_DRAW_SIZE) {
int32_t * s = lv_event_get_param(e);
*s = LV_MAX(*s, 20);
}
else if(code == LV_EVENT_DRAW_POST_END) {
int32_t id = lv_chart_get_pressed_point(chart);
if(id == LV_CHART_POINT_NONE) return;
LV_LOG_USER("Selected point %d", (int)id);
lv_chart_series_t * ser = lv_chart_get_series_next(chart, NULL);
while(ser) {
lv_point_t p;
lv_chart_get_point_pos_by_id(chart, ser, id, &p);
int32_t * y_array = lv_chart_get_y_array(chart, ser);
int32_t value = y_array[id];
/*Draw a rectangle above the clicked point*/
lv_layer_t * layer = lv_event_get_layer(e);
lv_draw_rect_dsc_t draw_rect_dsc;
lv_draw_rect_dsc_init(&draw_rect_dsc);
draw_rect_dsc.bg_color = lv_color_black();
draw_rect_dsc.bg_opa = LV_OPA_50;
draw_rect_dsc.radius = 3;
lv_area_t chart_obj_coords;
lv_obj_get_coords(chart, &chart_obj_coords);
lv_area_t rect_area;
rect_area.x1 = chart_obj_coords.x1 + p.x - 20;
rect_area.x2 = chart_obj_coords.x1 + p.x + 20;
rect_area.y1 = chart_obj_coords.y1 + p.y - 30;
rect_area.y2 = chart_obj_coords.y1 + p.y - 10;
lv_draw_rect(layer, &draw_rect_dsc, &rect_area);
/*Draw the value as label to the center of the rectangle*/
char buf[16];
lv_snprintf(buf, sizeof(buf), LV_SYMBOL_DUMMY"$%d", value);
lv_draw_label_dsc_t draw_label_dsc;
lv_draw_label_dsc_init(&draw_label_dsc);
draw_label_dsc.color = lv_color_white();
draw_label_dsc.text = buf;
draw_label_dsc.text_local = 1;
draw_label_dsc.align = LV_TEXT_ALIGN_CENTER;
lv_area_t label_area = rect_area;
lv_area_set_height(&label_area, lv_font_get_line_height(draw_label_dsc.font));
lv_area_align(&rect_area, &label_area, LV_ALIGN_CENTER, 0, 0);
lv_draw_label(layer, &draw_label_dsc, &label_area);
ser = lv_chart_get_series_next(chart, ser);
}
}
else if(code == LV_EVENT_RELEASED) {
lv_obj_invalidate(chart);
}
}
/**
* Show the value of the pressed points
*/
void lv_example_chart_3(void)
{
/*Create a chart*/
lv_obj_t * chart;
chart = lv_chart_create(lv_screen_active());
lv_obj_set_size(chart, 200, 150);
lv_obj_center(chart);
lv_obj_add_event_cb(chart, event_cb, LV_EVENT_ALL, NULL);
lv_obj_refresh_ext_draw_size(chart);
/*Zoom in a little in X*/
// lv_chart_set_scale_x(chart, 800);
/*Add two data series*/
lv_chart_series_t * ser1 = lv_chart_add_series(chart, lv_palette_main(LV_PALETTE_RED), LV_CHART_AXIS_PRIMARY_Y);
lv_chart_series_t * ser2 = lv_chart_add_series(chart, lv_palette_main(LV_PALETTE_GREEN), LV_CHART_AXIS_PRIMARY_Y);
uint32_t i;
for(i = 0; i < 10; i++) {
lv_chart_set_next_value(chart, ser1, lv_rand(60, 90));
lv_chart_set_next_value(chart, ser2, lv_rand(10, 40));
}
}
#endif
Recolor bars based on their value
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_CHART && LV_DRAW_SW_COMPLEX && LV_BUILD_EXAMPLES
static void draw_event_cb(lv_event_t * e)
{
lv_draw_task_t * draw_task = lv_event_get_draw_task(e);
lv_draw_dsc_base_t * base_dsc = lv_draw_task_get_draw_dsc(draw_task);
if(base_dsc->part != LV_PART_ITEMS) {
return;
}
lv_draw_fill_dsc_t * fill_dsc = lv_draw_task_get_fill_dsc(draw_task);
if(fill_dsc) {
lv_obj_t * chart = lv_event_get_target(e);
int32_t * y_array = lv_chart_get_y_array(chart, lv_chart_get_series_next(chart, NULL));
int32_t v = y_array[base_dsc->id2];
uint32_t ratio = v * 255 / 100;
fill_dsc->color = lv_color_mix(lv_palette_main(LV_PALETTE_GREEN), lv_palette_main(LV_PALETTE_RED), ratio);
}
}
/**
* Recolor the bars of a chart based on their value
*/
void lv_example_chart_4(void)
{
/*Create a chart1*/
lv_obj_t * chart = lv_chart_create(lv_screen_active());
lv_chart_set_type(chart, LV_CHART_TYPE_BAR);
lv_chart_set_point_count(chart, 24);
lv_obj_set_style_pad_column(chart, 2, 0);
lv_obj_set_size(chart, 260, 160);
lv_obj_center(chart);
lv_chart_series_t * ser = lv_chart_add_series(chart, lv_color_hex(0xff0000), LV_CHART_AXIS_PRIMARY_Y);
lv_obj_add_event_cb(chart, draw_event_cb, LV_EVENT_DRAW_TASK_ADDED, NULL);
lv_obj_add_flag(chart, LV_OBJ_FLAG_SEND_DRAW_TASK_EVENTS);
uint32_t i;
for(i = 0; i < 24; i++) {
lv_chart_set_next_value(chart, ser, lv_rand(10, 90));
}
}
#endif
Faded area line chart with custom division lines
C code
View on GitHub#include "../../lv_examples.h"
#include "../../../src/lvgl_private.h"
#if LV_USE_CHART && LV_DRAW_SW_COMPLEX && LV_BUILD_EXAMPLES
static void hook_division_lines(lv_event_t * e);
static void add_faded_area(lv_event_t * e);
static void draw_event_cb(lv_event_t * e);
/**
* Add a faded area effect to the line chart and make some division lines ticker
*/
void lv_example_chart_5(void)
{
/*Create a chart*/
lv_obj_t * chart = lv_chart_create(lv_screen_active());
lv_chart_set_type(chart, LV_CHART_TYPE_LINE); /*Show lines and points too*/
lv_obj_set_size(chart, 200, 150);
lv_obj_set_style_pad_all(chart, 0, 0);
lv_obj_set_style_radius(chart, 0, 0);
lv_obj_center(chart);
lv_chart_set_div_line_count(chart, 5, 7);
lv_obj_add_event_cb(chart, draw_event_cb, LV_EVENT_DRAW_TASK_ADDED, NULL);
lv_obj_add_flag(chart, LV_OBJ_FLAG_SEND_DRAW_TASK_EVENTS);
lv_chart_series_t * ser = lv_chart_add_series(chart, lv_palette_main(LV_PALETTE_RED), LV_CHART_AXIS_PRIMARY_Y);
uint32_t i;
for(i = 0; i < 10; i++) {
lv_chart_set_next_value(chart, ser, lv_rand(10, 80));
}
}
static void draw_event_cb(lv_event_t * e)
{
lv_draw_task_t * draw_task = lv_event_get_draw_task(e);
lv_draw_dsc_base_t * base_dsc = lv_draw_task_get_draw_dsc(draw_task);
if(base_dsc->part == LV_PART_ITEMS && lv_draw_task_get_type(draw_task) == LV_DRAW_TASK_TYPE_LINE) {
add_faded_area(e);
}
/*Hook the division lines too*/
if(base_dsc->part == LV_PART_MAIN && lv_draw_task_get_type(draw_task) == LV_DRAW_TASK_TYPE_LINE) {
hook_division_lines(e);
}
}
static void add_faded_area(lv_event_t * e)
{
lv_obj_t * obj = lv_event_get_target(e);
lv_area_t coords;
lv_obj_get_coords(obj, &coords);
lv_draw_task_t * draw_task = lv_event_get_draw_task(e);
lv_draw_dsc_base_t * base_dsc = lv_draw_task_get_draw_dsc(draw_task);
const lv_chart_series_t * ser = lv_chart_get_series_next(obj, NULL);
lv_color_t ser_color = lv_chart_get_series_color(obj, ser);
/*Draw a triangle below the line witch some opacity gradient*/
lv_draw_line_dsc_t * draw_line_dsc = lv_draw_task_get_draw_dsc(draw_task);
lv_draw_triangle_dsc_t tri_dsc;
lv_draw_triangle_dsc_init(&tri_dsc);
tri_dsc.p[0].x = draw_line_dsc->p1.x;
tri_dsc.p[0].y = draw_line_dsc->p1.y;
tri_dsc.p[1].x = draw_line_dsc->p2.x;
tri_dsc.p[1].y = draw_line_dsc->p2.y;
tri_dsc.p[2].x = draw_line_dsc->p1.y < draw_line_dsc->p2.y ? draw_line_dsc->p1.x : draw_line_dsc->p2.x;
tri_dsc.p[2].y = LV_MAX(draw_line_dsc->p1.y, draw_line_dsc->p2.y);
tri_dsc.bg_grad.dir = LV_GRAD_DIR_VER;
int32_t full_h = lv_obj_get_height(obj);
int32_t fract_uppter = (int32_t)(LV_MIN(draw_line_dsc->p1.y, draw_line_dsc->p2.y) - coords.y1) * 255 / full_h;
int32_t fract_lower = (int32_t)(LV_MAX(draw_line_dsc->p1.y, draw_line_dsc->p2.y) - coords.y1) * 255 / full_h;
tri_dsc.bg_grad.stops[0].color = ser_color;
tri_dsc.bg_grad.stops[0].opa = 255 - fract_uppter;
tri_dsc.bg_grad.stops[0].frac = 0;
tri_dsc.bg_grad.stops[1].color = ser_color;
tri_dsc.bg_grad.stops[1].opa = 255 - fract_lower;
tri_dsc.bg_grad.stops[1].frac = 255;
lv_draw_triangle(base_dsc->layer, &tri_dsc);
/*Draw rectangle below the triangle*/
lv_draw_rect_dsc_t rect_dsc;
lv_draw_rect_dsc_init(&rect_dsc);
rect_dsc.bg_grad.dir = LV_GRAD_DIR_VER;
rect_dsc.bg_grad.stops[0].color = ser_color;
rect_dsc.bg_grad.stops[0].frac = 0;
rect_dsc.bg_grad.stops[0].opa = 255 - fract_lower;
rect_dsc.bg_grad.stops[1].color = ser_color;
rect_dsc.bg_grad.stops[1].frac = 255;
rect_dsc.bg_grad.stops[1].opa = 0;
lv_area_t rect_area;
rect_area.x1 = (int32_t)draw_line_dsc->p1.x;
rect_area.x2 = (int32_t)draw_line_dsc->p2.x - 1;
rect_area.y1 = (int32_t)LV_MAX(draw_line_dsc->p1.y, draw_line_dsc->p2.y) - 1;
rect_area.y2 = (int32_t)coords.y2;
lv_draw_rect(base_dsc->layer, &rect_dsc, &rect_area);
}
static void hook_division_lines(lv_event_t * e)
{
lv_draw_task_t * draw_task = lv_event_get_draw_task(e);
lv_draw_dsc_base_t * base_dsc = lv_draw_task_get_draw_dsc(draw_task);
lv_draw_line_dsc_t * line_dsc = lv_draw_task_get_draw_dsc(draw_task);
/*Vertical line*/
if(line_dsc->p1.x == line_dsc->p2.x) {
line_dsc->color = lv_palette_lighten(LV_PALETTE_GREY, 1);
if(base_dsc->id1 == 3) {
line_dsc->width = 2;
line_dsc->dash_gap = 0;
line_dsc->dash_width = 0;
}
else {
line_dsc->width = 1;
line_dsc->dash_gap = 6;
line_dsc->dash_width = 6;
}
}
/*Horizontal line*/
else {
if(base_dsc->id1 == 2) {
line_dsc->width = 2;
line_dsc->dash_gap = 0;
line_dsc->dash_width = 0;
}
else {
line_dsc->width = 2;
line_dsc->dash_gap = 6;
line_dsc->dash_width = 6;
}
if(base_dsc->id1 == 1 || base_dsc->id1 == 3) {
line_dsc->color = lv_palette_main(LV_PALETTE_GREEN);
}
else {
line_dsc->color = lv_palette_lighten(LV_PALETTE_GREY, 1);
}
}
}
#endif
Show cursor on the clicked point
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_CHART && LV_BUILD_EXAMPLES
static lv_obj_t * chart;
static lv_chart_series_t * ser;
static lv_chart_cursor_t * cursor;
static void value_changed_event_cb(lv_event_t * e)
{
static int32_t last_id = -1;
lv_obj_t * obj = lv_event_get_target(e);
last_id = lv_chart_get_pressed_point(obj);
if(last_id != LV_CHART_POINT_NONE) {
lv_chart_set_cursor_point(obj, cursor, NULL, last_id);
}
}
/**
* Show cursor on the clicked point
*/
void lv_example_chart_6(void)
{
chart = lv_chart_create(lv_screen_active());
lv_obj_set_size(chart, 200, 150);
lv_obj_align(chart, LV_ALIGN_CENTER, 0, -10);
// lv_chart_set_axis_tick(chart, LV_CHART_AXIS_PRIMARY_Y, 10, 5, 6, 5, true, 40);
// lv_chart_set_axis_tick(chart, LV_CHART_AXIS_PRIMARY_X, 10, 5, 10, 1, true, 30);
lv_obj_add_event_cb(chart, value_changed_event_cb, LV_EVENT_VALUE_CHANGED, NULL);
lv_obj_refresh_ext_draw_size(chart);
cursor = lv_chart_add_cursor(chart, lv_palette_main(LV_PALETTE_BLUE), LV_DIR_LEFT | LV_DIR_BOTTOM);
ser = lv_chart_add_series(chart, lv_palette_main(LV_PALETTE_RED), LV_CHART_AXIS_PRIMARY_Y);
uint32_t i;
for(i = 0; i < 10; i++) {
lv_chart_set_next_value(chart, ser, lv_rand(10, 90));
}
// lv_chart_set_scale_x(chart, 500);
lv_obj_t * label = lv_label_create(lv_screen_active());
lv_label_set_text(label, "Click on a point");
lv_obj_align_to(label, chart, LV_ALIGN_OUT_TOP_MID, 0, -5);
}
#endif
Scatter chart
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_CHART && LV_BUILD_EXAMPLES
static void draw_event_cb(lv_event_t * e)
{
lv_draw_task_t * draw_task = lv_event_get_draw_task(e);
lv_draw_dsc_base_t * base_dsc = lv_draw_task_get_draw_dsc(draw_task);
if(base_dsc->part == LV_PART_INDICATOR) {
lv_obj_t * obj = lv_event_get_target(e);
lv_chart_series_t * ser = lv_chart_get_series_next(obj, NULL);
lv_draw_rect_dsc_t * rect_draw_dsc = lv_draw_task_get_draw_dsc(draw_task);
uint32_t cnt = lv_chart_get_point_count(obj);
/*Make older value more transparent*/
rect_draw_dsc->bg_opa = (LV_OPA_COVER * base_dsc->id2) / (cnt - 1);
/*Make smaller values blue, higher values red*/
int32_t * x_array = lv_chart_get_x_array(obj, ser);
int32_t * y_array = lv_chart_get_y_array(obj, ser);
/*dsc->id is the tells drawing order, but we need the ID of the point being drawn.*/
uint32_t start_point = lv_chart_get_x_start_point(obj, ser);
uint32_t p_act = (start_point + base_dsc->id2) % cnt; /*Consider start point to get the index of the array*/
lv_opa_t x_opa = (x_array[p_act] * LV_OPA_50) / 200;
lv_opa_t y_opa = (y_array[p_act] * LV_OPA_50) / 1000;
rect_draw_dsc->bg_color = lv_color_mix(lv_palette_main(LV_PALETTE_RED),
lv_palette_main(LV_PALETTE_BLUE),
x_opa + y_opa);
}
}
static void add_data(lv_timer_t * timer)
{
lv_obj_t * chart = lv_timer_get_user_data(timer);
lv_chart_set_next_value2(chart, lv_chart_get_series_next(chart, NULL), lv_rand(0, 200), lv_rand(0, 1000));
}
/**
* A scatter chart
*/
void lv_example_chart_7(void)
{
lv_obj_t * chart = lv_chart_create(lv_screen_active());
lv_obj_set_size(chart, 200, 150);
lv_obj_align(chart, LV_ALIGN_CENTER, 0, 0);
lv_obj_add_event_cb(chart, draw_event_cb, LV_EVENT_DRAW_TASK_ADDED, NULL);
lv_obj_add_flag(chart, LV_OBJ_FLAG_SEND_DRAW_TASK_EVENTS);
lv_obj_set_style_line_width(chart, 0, LV_PART_ITEMS); /*Remove the lines*/
lv_chart_set_type(chart, LV_CHART_TYPE_SCATTER);
lv_chart_set_range(chart, LV_CHART_AXIS_PRIMARY_X, 0, 200);
lv_chart_set_range(chart, LV_CHART_AXIS_PRIMARY_Y, 0, 1000);
lv_chart_set_point_count(chart, 50);
lv_chart_series_t * ser = lv_chart_add_series(chart, lv_palette_main(LV_PALETTE_RED), LV_CHART_AXIS_PRIMARY_Y);
uint32_t i;
for(i = 0; i < 50; i++) {
lv_chart_set_next_value2(chart, ser, lv_rand(0, 200), lv_rand(0, 1000));
}
lv_timer_create(add_data, 100, chart);
}
#endif
Circular line chart with gap
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_CHART && LV_DRAW_SW_COMPLEX && LV_BUILD_EXAMPLES
static void add_data(lv_timer_t * t)
{
lv_obj_t * chart = lv_timer_get_user_data(t);
lv_chart_series_t * ser = lv_chart_get_series_next(chart, NULL);
lv_chart_set_next_value(chart, ser, lv_rand(10, 90));
uint16_t p = lv_chart_get_point_count(chart);
uint16_t s = lv_chart_get_x_start_point(chart, ser);
int32_t * a = lv_chart_get_y_array(chart, ser);
a[(s + 1) % p] = LV_CHART_POINT_NONE;
a[(s + 2) % p] = LV_CHART_POINT_NONE;
a[(s + 2) % p] = LV_CHART_POINT_NONE;
lv_chart_refresh(chart);
}
/**
* Circular line chart with gap
*/
void lv_example_chart_8(void)
{
/*Create a stacked_area_chart.obj*/
lv_obj_t * chart = lv_chart_create(lv_screen_active());
lv_chart_set_update_mode(chart, LV_CHART_UPDATE_MODE_CIRCULAR);
lv_obj_set_style_size(chart, 0, 0, LV_PART_INDICATOR);
lv_obj_set_size(chart, 280, 150);
lv_obj_center(chart);
lv_chart_set_point_count(chart, 80);
lv_chart_series_t * ser = lv_chart_add_series(chart, lv_palette_main(LV_PALETTE_RED), LV_CHART_AXIS_PRIMARY_Y);
/*Prefill with data*/
uint32_t i;
for(i = 0; i < 80; i++) {
lv_chart_set_next_value(chart, ser, lv_rand(10, 90));
}
lv_timer_create(add_data, 300, chart);
}
#endif
Checkbox（复选框）
Simple Checkboxes
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_CHECKBOX && LV_BUILD_EXAMPLES
static void event_handler(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * obj = lv_event_get_target(e);
if(code == LV_EVENT_VALUE_CHANGED) {
LV_UNUSED(obj);
const char * txt = lv_checkbox_get_text(obj);
const char * state = lv_obj_get_state(obj) & LV_STATE_CHECKED ? "Checked" : "Unchecked";
LV_UNUSED(txt);
LV_UNUSED(state);
LV_LOG_USER("%s: %s", txt, state);
}
}
void lv_example_checkbox_1(void)
{
lv_obj_set_flex_flow(lv_screen_active(), LV_FLEX_FLOW_COLUMN);
lv_obj_set_flex_align(lv_screen_active(), LV_FLEX_ALIGN_CENTER, LV_FLEX_ALIGN_START, LV_FLEX_ALIGN_CENTER);
lv_obj_t * cb;
cb = lv_checkbox_create(lv_screen_active());
lv_checkbox_set_text(cb, "Apple");
lv_obj_add_event_cb(cb, event_handler, LV_EVENT_ALL, NULL);
cb = lv_checkbox_create(lv_screen_active());
lv_checkbox_set_text(cb, "Banana");
lv_obj_add_state(cb, LV_STATE_CHECKED);
lv_obj_add_event_cb(cb, event_handler, LV_EVENT_ALL, NULL);
cb = lv_checkbox_create(lv_screen_active());
lv_checkbox_set_text(cb, "Lemon");
lv_obj_add_state(cb, LV_STATE_DISABLED);
lv_obj_add_event_cb(cb, event_handler, LV_EVENT_ALL, NULL);
cb = lv_checkbox_create(lv_screen_active());
lv_obj_add_state(cb, LV_STATE_CHECKED | LV_STATE_DISABLED);
lv_checkbox_set_text(cb, "Melon\nand a new line");
lv_obj_add_event_cb(cb, event_handler, LV_EVENT_ALL, NULL);
lv_obj_update_layout(cb);
}
#endif
Colorwheel（色轮）
Dropdown（下拉列表）
Simple Drop down list
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_DROPDOWN && LV_BUILD_EXAMPLES
static void event_handler(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * obj = lv_event_get_target(e);
if(code == LV_EVENT_VALUE_CHANGED) {
char buf[32];
lv_dropdown_get_selected_str(obj, buf, sizeof(buf));
LV_LOG_USER("Option: %s", buf);
}
}
void lv_example_dropdown_1(void)
{
/*Create a normal drop down list*/
lv_obj_t * dd = lv_dropdown_create(lv_screen_active());
lv_dropdown_set_options(dd, "Apple\n"
"Banana\n"
"Orange\n"
"Cherry\n"
"Grape\n"
"Raspberry\n"
"Melon\n"
"Orange\n"
"Lemon\n"
"Nuts");
lv_obj_align(dd, LV_ALIGN_TOP_MID, 0, 20);
lv_obj_add_event_cb(dd, event_handler, LV_EVENT_ALL, NULL);
}
#endif
Drop down in four directions
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_DROPDOWN && LV_BUILD_EXAMPLES
/**
* Create a drop down, up, left and right menus
*/
void lv_example_dropdown_2(void)
{
static const char * opts = "Apple\n"
"Banana\n"
"Orange\n"
"Melon";
lv_obj_t * dd;
dd = lv_dropdown_create(lv_screen_active());
lv_dropdown_set_options_static(dd, opts);
lv_obj_align(dd, LV_ALIGN_TOP_MID, 0, 10);
dd = lv_dropdown_create(lv_screen_active());
lv_dropdown_set_options_static(dd, opts);
lv_dropdown_set_dir(dd, LV_DIR_BOTTOM);
lv_dropdown_set_symbol(dd, LV_SYMBOL_UP);
lv_obj_align(dd, LV_ALIGN_BOTTOM_MID, 0, -10);
dd = lv_dropdown_create(lv_screen_active());
lv_dropdown_set_options_static(dd, opts);
lv_dropdown_set_dir(dd, LV_DIR_RIGHT);
lv_dropdown_set_symbol(dd, LV_SYMBOL_RIGHT);
lv_obj_align(dd, LV_ALIGN_LEFT_MID, 10, 0);
dd = lv_dropdown_create(lv_screen_active());
lv_dropdown_set_options_static(dd, opts);
lv_dropdown_set_dir(dd, LV_DIR_LEFT);
lv_dropdown_set_symbol(dd, LV_SYMBOL_LEFT);
lv_obj_align(dd, LV_ALIGN_RIGHT_MID, -10, 0);
}
#endif
Image（图像）
Keyboard（键盘）
Keyboard with text area
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_KEYBOARD && LV_BUILD_EXAMPLES
static void ta_event_cb(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * ta = lv_event_get_target(e);
lv_obj_t * kb = lv_event_get_user_data(e);
if(code == LV_EVENT_FOCUSED) {
lv_keyboard_set_textarea(kb, ta);
lv_obj_remove_flag(kb, LV_OBJ_FLAG_HIDDEN);
}
if(code == LV_EVENT_DEFOCUSED) {
lv_keyboard_set_textarea(kb, NULL);
lv_obj_add_flag(kb, LV_OBJ_FLAG_HIDDEN);
}
}
void lv_example_keyboard_1(void)
{
/*Create a keyboard to use it with an of the text areas*/
lv_obj_t * kb = lv_keyboard_create(lv_screen_active());
/*Create a text area. The keyboard will write here*/
lv_obj_t * ta1;
ta1 = lv_textarea_create(lv_screen_active());
lv_obj_align(ta1, LV_ALIGN_TOP_LEFT, 10, 10);
lv_obj_add_event_cb(ta1, ta_event_cb, LV_EVENT_ALL, kb);
lv_textarea_set_placeholder_text(ta1, "Hello");
lv_obj_set_size(ta1, 140, 80);
lv_obj_t * ta2;
ta2 = lv_textarea_create(lv_screen_active());
lv_obj_align(ta2, LV_ALIGN_TOP_RIGHT, -10, 10);
lv_obj_add_event_cb(ta2, ta_event_cb, LV_EVENT_ALL, kb);
lv_obj_set_size(ta2, 140, 80);
lv_keyboard_set_textarea(kb, ta1);
/*The keyboard will show Arabic characters if they are enabled */
#if LV_USE_ARABIC_PERSIAN_CHARS && LV_FONT_DEJAVU_16_PERSIAN_HEBREW
lv_obj_set_style_text_font(kb, &lv_font_dejavu_16_persian_hebrew, 0);
lv_obj_set_style_text_font(ta1, &lv_font_dejavu_16_persian_hebrew, 0);
lv_obj_set_style_text_font(ta2, &lv_font_dejavu_16_persian_hebrew, 0);
#endif
}
#endif
Keyboard with custom map
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_KEYBOARD && LV_BUILD_EXAMPLES
void lv_example_keyboard_2(void)
{
/*Create an AZERTY keyboard map*/
static const char * kb_map[] = {"A", "Z", "E", "R", "T", "Y", "U", "I", "O", "P", LV_SYMBOL_BACKSPACE, "\n",
"Q", "S", "D", "F", "G", "J", "K", "L", "M", LV_SYMBOL_NEW_LINE, "\n",
"W", "X", "C", "V", "B", "N", ",", ".", ":", "!", "?", "\n",
LV_SYMBOL_CLOSE, " ", " ", " ", LV_SYMBOL_OK, NULL
};
/*Set the relative width of the buttons and other controls*/
static const lv_buttonmatrix_ctrl_t kb_ctrl[] = {4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 6,
4, 4, 4, 4, 4, 4, 4, 4, 4, 6,
4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
2, LV_BUTTONMATRIX_CTRL_HIDDEN | 2, 6, LV_BUTTONMATRIX_CTRL_HIDDEN | 2, 2
};
/*Create a keyboard and add the new map as USER_1 mode*/
lv_obj_t * kb = lv_keyboard_create(lv_screen_active());
lv_keyboard_set_map(kb, LV_KEYBOARD_MODE_USER_1, kb_map, kb_ctrl);
lv_keyboard_set_mode(kb, LV_KEYBOARD_MODE_USER_1);
/*Create a text area. The keyboard will write here*/
lv_obj_t * ta;
ta = lv_textarea_create(lv_screen_active());
lv_obj_align(ta, LV_ALIGN_TOP_MID, 0, 10);
lv_obj_set_size(ta, lv_pct(90), 80);
lv_obj_add_state(ta, LV_STATE_FOCUSED);
lv_keyboard_set_textarea(kb, ta);
}
#endif
Label（标签）
Line wrap, recoloring and scrolling
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_LABEL && LV_BUILD_EXAMPLES
/**
* Show line wrap, re-color, line align and text scrolling.
*/
void lv_example_label_1(void)
{
lv_obj_t * label1 = lv_label_create(lv_screen_active());
lv_label_set_long_mode(label1, LV_LABEL_LONG_WRAP); /*Break the long lines*/
lv_label_set_text(label1, "Recolor is not supported for v9 now.");
lv_obj_set_width(label1, 150); /*Set smaller width to make the lines wrap*/
lv_obj_set_style_text_align(label1, LV_TEXT_ALIGN_CENTER, 0);
lv_obj_align(label1, LV_ALIGN_CENTER, 0, -40);
lv_obj_t * label2 = lv_label_create(lv_screen_active());
lv_label_set_long_mode(label2, LV_LABEL_LONG_SCROLL_CIRCULAR); /*Circular scroll*/
lv_obj_set_width(label2, 150);
lv_label_set_text(label2, "It is a circularly scrolling text. ");
lv_obj_align(label2, LV_ALIGN_CENTER, 0, 40);
}
#endif
Text shadow
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_LABEL && LV_BUILD_EXAMPLES
/**
* Create a fake text shadow
*/
void lv_example_label_2(void)
{
/*Create a style for the shadow*/
static lv_style_t style_shadow;
lv_style_init(&style_shadow);
lv_style_set_text_opa(&style_shadow, LV_OPA_30);
lv_style_set_text_color(&style_shadow, lv_color_black());
/*Create a label for the shadow first (it's in the background)*/
lv_obj_t * shadow_label = lv_label_create(lv_screen_active());
lv_obj_add_style(shadow_label, &style_shadow, 0);
/*Create the main label*/
lv_obj_t * main_label = lv_label_create(lv_screen_active());
lv_label_set_text(main_label, "A simple method to create\n"
"shadows on a text.\n"
"It even works with\n\n"
"newlines and spaces.");
/*Set the same text for the shadow label*/
lv_label_set_text(shadow_label, lv_label_get_text(main_label));
/*Position the main label*/
lv_obj_align(main_label, LV_ALIGN_CENTER, 0, 0);
/*Shift the second label down and to the right by 2 pixel*/
lv_obj_align_to(shadow_label, main_label, LV_ALIGN_TOP_LEFT, 2, 2);
}
#endif
Show LTR, RTL and Chinese texts
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_LABEL && LV_BUILD_EXAMPLES && LV_FONT_DEJAVU_16_PERSIAN_HEBREW && LV_FONT_SIMSUN_16_CJK && LV_USE_BIDI
/**
* Show mixed LTR, RTL and Chinese label
*/
void lv_example_label_3(void)
{
lv_obj_t * ltr_label = lv_label_create(lv_screen_active());
lv_label_set_text(ltr_label, "In modern terminology, a microcontroller is similar to a system on a chip (SoC).");
lv_obj_set_style_text_font(ltr_label, &lv_font_montserrat_16, 0);
lv_obj_set_width(ltr_label, 310);
lv_obj_align(ltr_label, LV_ALIGN_TOP_LEFT, 5, 5);
lv_obj_t * rtl_label = lv_label_create(lv_screen_active());
lv_label_set_text(rtl_label,
"מעבד, או בשמו המלא יחידת עיבוד מרכזית (באנגלית: CPU - Central Processing Unit).");
lv_obj_set_style_base_dir(rtl_label, LV_BASE_DIR_RTL, 0);
lv_obj_set_style_text_font(rtl_label, &lv_font_dejavu_16_persian_hebrew, 0);
lv_obj_set_width(rtl_label, 310);
lv_obj_align(rtl_label, LV_ALIGN_LEFT_MID, 5, 0);
lv_obj_t * cz_label = lv_label_create(lv_screen_active());
lv_label_set_text(cz_label,
"嵌入式系统（Embedded System），\n是一种嵌入机械或电气系统内部、具有专一功能和实时计算性能的计算机系统。");
lv_obj_set_style_text_font(cz_label, &lv_font_simsun_16_cjk, 0);
lv_obj_set_width(cz_label, 310);
lv_obj_align(cz_label, LV_ALIGN_BOTTOM_LEFT, 5, -5);
}
#endif
Draw label with gradient color
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_LABEL && LV_FONT_MONTSERRAT_24 && LV_USE_CANVAS && LV_BUILD_EXAMPLES && LV_DRAW_SW_COMPLEX
#define MASK_WIDTH 150
#define MASK_HEIGHT 60
static void generate_mask(lv_draw_buf_t * mask, int32_t w, int32_t h, const char * txt)
{
/*Create a "8 bit alpha" canvas and clear it*/
lv_obj_t * canvas = lv_canvas_create(lv_screen_active());
lv_canvas_set_draw_buf(canvas, mask);
lv_canvas_fill_bg(canvas, lv_color_black(), LV_OPA_TRANSP);
lv_layer_t layer;
lv_canvas_init_layer(canvas, &layer);
/*Draw a label to the canvas. The result "image" will be used as mask*/
lv_draw_label_dsc_t label_dsc;
lv_draw_label_dsc_init(&label_dsc);
label_dsc.color = lv_color_white();
label_dsc.align = LV_TEXT_ALIGN_CENTER;
label_dsc.text = txt;
label_dsc.font = &lv_font_montserrat_24;
lv_area_t a = {0, 0, w - 1, h - 1};
lv_draw_label(&layer, &label_dsc, &a);
lv_canvas_finish_layer(canvas, &layer);
lv_obj_delete(canvas);
}
/**
* Draw label with gradient color
*/
void lv_example_label_4(void)
{
/* Create the mask of a text by drawing it to a canvas*/
LV_DRAW_BUF_DEFINE_STATIC(mask, MASK_WIDTH, MASK_HEIGHT, LV_COLOR_FORMAT_L8);
LV_DRAW_BUF_INIT_STATIC(mask);
generate_mask(&mask, MASK_WIDTH, MASK_HEIGHT, "Text with gradient");
/* Create an object from where the text will be masked out.
* Now it's a rectangle with a gradient but it could be an image too*/
lv_obj_t * grad = lv_obj_create(lv_screen_active());
lv_obj_set_size(grad, MASK_WIDTH, MASK_HEIGHT);
lv_obj_center(grad);
lv_obj_set_style_bg_color(grad, lv_color_hex(0xff0000), 0);
lv_obj_set_style_bg_grad_color(grad, lv_color_hex(0x0000ff), 0);
lv_obj_set_style_bg_grad_dir(grad, LV_GRAD_DIR_HOR, 0);
lv_obj_set_style_bitmap_mask_src(grad, &mask, 0);
}
#endif
Customize circular scrolling animation
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_LABEL && LV_BUILD_EXAMPLES
/**
* Show customizing the circular scrolling animation of a label with `LV_LABEL_LONG_SCROLL_CIRCULAR`
* long mode.
*/
void lv_example_label_5(void)
{
static lv_anim_t animation_template;
static lv_style_t label_style;
lv_anim_init(&animation_template);
lv_anim_set_delay(&animation_template, 1000); /*Wait 1 second to start the first scroll*/
lv_anim_set_repeat_delay(&animation_template,
3000); /*Repeat the scroll 3 seconds after the label scrolls back to the initial position*/
/*Initialize the label style with the animation template*/
lv_style_init(&label_style);
lv_style_set_anim(&label_style, &animation_template);
lv_obj_t * label1 = lv_label_create(lv_screen_active());
lv_label_set_long_mode(label1, LV_LABEL_LONG_SCROLL_CIRCULAR); /*Circular scroll*/
lv_obj_set_width(label1, 150);
lv_label_set_text(label1, "It is a circularly scrolling text. ");
lv_obj_align(label1, LV_ALIGN_CENTER, 0, 40);
lv_obj_add_style(label1, &label_style, LV_STATE_DEFAULT); /*Add the style to the label*/
}
#endif
LED（指示灯）
LED with custom style
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_LED && LV_BUILD_EXAMPLES
/**
* Create LED's with different brightness and color
*/
void lv_example_led_1(void)
{
/*Create a LED and switch it OFF*/
lv_obj_t * led1 = lv_led_create(lv_screen_active());
lv_obj_align(led1, LV_ALIGN_CENTER, -80, 0);
lv_led_off(led1);
/*Copy the previous LED and set a brightness*/
lv_obj_t * led2 = lv_led_create(lv_screen_active());
lv_obj_align(led2, LV_ALIGN_CENTER, 0, 0);
lv_led_set_brightness(led2, 150);
lv_led_set_color(led2, lv_palette_main(LV_PALETTE_RED));
/*Copy the previous LED and switch it ON*/
lv_obj_t * led3 = lv_led_create(lv_screen_active());
lv_obj_align(led3, LV_ALIGN_CENTER, 80, 0);
lv_led_on(led3);
}
#endif
Line（线条）
Simple Line
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_LINE && LV_BUILD_EXAMPLES
void lv_example_line_1(void)
{
/*Create an array for the points of the line*/
static lv_point_precise_t line_points[] = { {5, 5}, {70, 70}, {120, 10}, {180, 60}, {240, 10} };
/*Create style*/
static lv_style_t style_line;
lv_style_init(&style_line);
lv_style_set_line_width(&style_line, 8);
lv_style_set_line_color(&style_line, lv_palette_main(LV_PALETTE_BLUE));
lv_style_set_line_rounded(&style_line, true);
/*Create a line and apply the new style*/
lv_obj_t * line1;
line1 = lv_line_create(lv_screen_active());
lv_line_set_points(line1, line_points, 5); /*Set the points*/
lv_obj_add_style(line1, &style_line, 0);
lv_obj_center(line1);
}
#endif
List（列表）
Simple List
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_LIST && LV_BUILD_EXAMPLES
static lv_obj_t * list1;
static void event_handler(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * obj = lv_event_get_target(e);
if(code == LV_EVENT_CLICKED) {
LV_UNUSED(obj);
LV_LOG_USER("Clicked: %s", lv_list_get_button_text(list1, obj));
}
}
void lv_example_list_1(void)
{
/*Create a list*/
list1 = lv_list_create(lv_screen_active());
lv_obj_set_size(list1, 180, 220);
lv_obj_center(list1);
/*Add buttons to the list*/
lv_obj_t * btn;
lv_list_add_text(list1, "File");
btn = lv_list_add_button(list1, LV_SYMBOL_FILE, "New");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_list_add_button(list1, LV_SYMBOL_DIRECTORY, "Open");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_list_add_button(list1, LV_SYMBOL_SAVE, "Save");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_list_add_button(list1, LV_SYMBOL_CLOSE, "Delete");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_list_add_button(list1, LV_SYMBOL_EDIT, "Edit");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
lv_list_add_text(list1, "Connectivity");
btn = lv_list_add_button(list1, LV_SYMBOL_BLUETOOTH, "Bluetooth");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_list_add_button(list1, LV_SYMBOL_GPS, "Navigation");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_list_add_button(list1, LV_SYMBOL_USB, "USB");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_list_add_button(list1, LV_SYMBOL_BATTERY_FULL, "Battery");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
lv_list_add_text(list1, "Exit");
btn = lv_list_add_button(list1, LV_SYMBOL_OK, "Apply");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_list_add_button(list1, LV_SYMBOL_CLOSE, "Close");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
}
#endif
Menu（菜单）
Meter（仪表）
Message box（消息框）
Simple Message box
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_MSGBOX && LV_BUILD_EXAMPLES
static void event_cb(lv_event_t * e)
{
lv_obj_t * btn = lv_event_get_target(e);
lv_obj_t * label = lv_obj_get_child(btn, 0);
LV_UNUSED(label);
LV_LOG_USER("Button %s clicked", lv_label_get_text(label));
}
void lv_example_msgbox_1(void)
{
lv_obj_t * mbox1 = lv_msgbox_create(NULL);
lv_msgbox_add_title(mbox1, "Hello");
lv_msgbox_add_text(mbox1, "This is a message box with two buttons.");
lv_msgbox_add_close_button(mbox1);
lv_obj_t * btn;
btn = lv_msgbox_add_footer_button(mbox1, "Apply");
lv_obj_add_event_cb(btn, event_cb, LV_EVENT_CLICKED, NULL);
btn = lv_msgbox_add_footer_button(mbox1, "Cancel");
lv_obj_add_event_cb(btn, event_cb, LV_EVENT_CLICKED, NULL);
return;
}
#endif
Scrolling and styled Message box
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_MSGBOX && LV_BUILD_EXAMPLES
static void minimize_button_event_cb(lv_event_t * e)
{
lv_obj_t * mbox = (lv_obj_t *) lv_event_get_user_data(e);
lv_obj_add_flag(mbox, LV_OBJ_FLAG_HIDDEN);
}
void lv_example_msgbox_2(void)
{
lv_obj_t * setting = lv_msgbox_create(lv_screen_active());
lv_obj_set_style_clip_corner(setting, true, 0);
/* setting fixed size */
lv_obj_set_size(setting, 300, 200);
/* setting's titlebar/header */
lv_msgbox_add_title(setting, "Setting");
lv_obj_t * minimize_button = lv_msgbox_add_header_button(setting, LV_SYMBOL_MINUS);
lv_obj_add_event_cb(minimize_button, minimize_button_event_cb, LV_EVENT_CLICKED, setting);
lv_msgbox_add_close_button(setting);
/* setting's content*/
lv_obj_t * content = lv_msgbox_get_content(setting);
lv_obj_set_flex_flow(content, LV_FLEX_FLOW_COLUMN);
lv_obj_set_flex_align(content, LV_FLEX_ALIGN_START, LV_FLEX_ALIGN_CENTER, LV_FLEX_ALIGN_CENTER);
lv_obj_set_style_pad_right(content, -1, LV_PART_SCROLLBAR);
lv_obj_t * cont_brightness = lv_obj_create(content);
lv_obj_set_size(cont_brightness, lv_pct(100), LV_SIZE_CONTENT);
lv_obj_set_flex_flow(cont_brightness, LV_FLEX_FLOW_COLUMN);
lv_obj_set_flex_align(cont_brightness, LV_FLEX_ALIGN_CENTER, LV_FLEX_ALIGN_START, LV_FLEX_ALIGN_CENTER);
lv_obj_t * lb_brightness = lv_label_create(cont_brightness);
lv_label_set_text(lb_brightness, "Brightness : ");
lv_obj_t * slider_brightness = lv_slider_create(cont_brightness);
lv_obj_set_width(slider_brightness, lv_pct(100));
lv_slider_set_value(slider_brightness, 50, LV_ANIM_OFF);
lv_obj_t * cont_speed = lv_obj_create(content);
lv_obj_set_size(cont_speed, lv_pct(100), LV_SIZE_CONTENT);
lv_obj_set_flex_flow(cont_speed, LV_FLEX_FLOW_COLUMN);
lv_obj_set_flex_align(cont_speed, LV_FLEX_ALIGN_CENTER, LV_FLEX_ALIGN_START, LV_FLEX_ALIGN_CENTER);
lv_obj_t * lb_speed = lv_label_create(cont_speed);
lv_label_set_text(lb_speed, "Speed : ");
lv_obj_t * slider_speed = lv_slider_create(cont_speed);
lv_obj_set_width(slider_speed, lv_pct(100));
lv_slider_set_value(slider_speed, 80, LV_ANIM_OFF);
/* footer */
lv_obj_t * apply_button = lv_msgbox_add_footer_button(setting, "Apply");
lv_obj_set_flex_grow(apply_button, 1);
lv_obj_t * cancel_button = lv_msgbox_add_footer_button(setting, "Cancel");
lv_obj_set_flex_grow(cancel_button, 1);
lv_obj_t * footer = lv_msgbox_get_footer(setting);
lv_obj_set_style_bg_color(footer, lv_palette_main(LV_PALETTE_INDIGO), 0);
lv_obj_set_style_bg_opa(footer, LV_OPA_100, 0);
}
#endif
Roller（滚轮）
Simple Roller
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_ROLLER && LV_BUILD_EXAMPLES
static void event_handler(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * obj = lv_event_get_target(e);
if(code == LV_EVENT_VALUE_CHANGED) {
char buf[32];
lv_roller_get_selected_str(obj, buf, sizeof(buf));
LV_LOG_USER("Selected month: %s\n", buf);
}
}
/**
* An infinite roller with the name of the months
*/
void lv_example_roller_1(void)
{
lv_obj_t * roller1 = lv_roller_create(lv_screen_active());
lv_roller_set_options(roller1,
"January\n"
"February\n"
"March\n"
"April\n"
"May\n"
"June\n"
"July\n"
"August\n"
"September\n"
"October\n"
"November\n"
"December",
LV_ROLLER_MODE_INFINITE);
lv_roller_set_visible_row_count(roller1, 4);
lv_obj_center(roller1);
lv_obj_add_event_cb(roller1, event_handler, LV_EVENT_ALL, NULL);
}
#endif
Styling the roller
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_ROLLER && LV_FONT_MONTSERRAT_22 && LV_BUILD_EXAMPLES
static void event_handler(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * obj = lv_event_get_target(e);
if(code == LV_EVENT_VALUE_CHANGED) {
char buf[32];
lv_roller_get_selected_str(obj, buf, sizeof(buf));
LV_LOG_USER("Selected value: %s", buf);
}
}
/**
* Roller with various alignments and larger text in the selected area
*/
void lv_example_roller_2(void)
{
/*A style to make the selected option larger*/
static lv_style_t style_sel;
lv_style_init(&style_sel);
lv_style_set_text_font(&style_sel, &lv_font_montserrat_22);
lv_style_set_bg_color(&style_sel, lv_color_hex3(0xf88));
lv_style_set_border_width(&style_sel, 2);
lv_style_set_border_color(&style_sel, lv_color_hex3(0xf00));
const char * opts = "1\n2\n3\n4\n5\n6\n7\n8\n9\n10";
lv_obj_t * roller;
/*A roller on the left with left aligned text, and custom width*/
roller = lv_roller_create(lv_screen_active());
lv_roller_set_options(roller, opts, LV_ROLLER_MODE_NORMAL);
lv_roller_set_visible_row_count(roller, 2);
lv_obj_set_width(roller, 100);
lv_obj_add_style(roller, &style_sel, LV_PART_SELECTED);
lv_obj_set_style_text_align(roller, LV_TEXT_ALIGN_LEFT, 0);
lv_obj_set_style_bg_color(roller, lv_color_hex3(0x0f0), 0);
lv_obj_set_style_bg_grad_color(roller, lv_color_hex3(0xafa), 0);
lv_obj_set_style_bg_grad_dir(roller, LV_GRAD_DIR_VER, 0);
lv_obj_align(roller, LV_ALIGN_LEFT_MID, 10, 0);
lv_obj_add_event_cb(roller, event_handler, LV_EVENT_ALL, NULL);
lv_roller_set_selected(roller, 2, LV_ANIM_OFF);
/*A roller on the middle with center aligned text, and auto (default) width*/
roller = lv_roller_create(lv_screen_active());
lv_roller_set_options(roller, opts, LV_ROLLER_MODE_NORMAL);
lv_roller_set_visible_row_count(roller, 3);
lv_obj_add_style(roller, &style_sel, LV_PART_SELECTED);
lv_obj_align(roller, LV_ALIGN_CENTER, 0, 0);
lv_obj_add_event_cb(roller, event_handler, LV_EVENT_ALL, NULL);
lv_roller_set_selected(roller, 5, LV_ANIM_OFF);
/*A roller on the right with right aligned text, and custom width*/
roller = lv_roller_create(lv_screen_active());
lv_roller_set_options(roller, opts, LV_ROLLER_MODE_NORMAL);
lv_roller_set_visible_row_count(roller, 4);
lv_obj_set_width(roller, 80);
lv_obj_add_style(roller, &style_sel, LV_PART_SELECTED);
lv_obj_set_style_text_align(roller, LV_TEXT_ALIGN_RIGHT, 0);
lv_obj_align(roller, LV_ALIGN_RIGHT_MID, -10, 0);
lv_obj_add_event_cb(roller, event_handler, LV_EVENT_ALL, NULL);
lv_roller_set_selected(roller, 8, LV_ANIM_OFF);
}
#endif
add fade mask to roller
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_ROLLER && LV_DRAW_SW_COMPLEX && LV_BUILD_EXAMPLES && 1
static void generate_mask(lv_draw_buf_t * mask)
{
/*Create a "8 bit alpha" canvas and clear it*/
lv_obj_t * canvas = lv_canvas_create(lv_screen_active());
lv_canvas_set_draw_buf(canvas, mask);
lv_canvas_fill_bg(canvas, lv_color_white(), LV_OPA_TRANSP);
lv_layer_t layer;
lv_canvas_init_layer(canvas, &layer);
/*Draw a label to the canvas. The result "image" will be used as mask*/
lv_draw_rect_dsc_t rect_dsc;
lv_draw_rect_dsc_init(&rect_dsc);
rect_dsc.bg_grad.dir = LV_GRAD_DIR_VER;
rect_dsc.bg_grad.stops[0].color = lv_color_black();
rect_dsc.bg_grad.stops[1].color = lv_color_white();
rect_dsc.bg_grad.stops[0].opa = LV_OPA_COVER;
rect_dsc.bg_grad.stops[1].opa = LV_OPA_COVER;
lv_area_t a = {0, 0, mask->header.w - 1, mask->header.h / 2 - 10};
lv_draw_rect(&layer, &rect_dsc, &a);
a.y1 = mask->header.h / 2 + 10;
a.y2 = mask->header.h - 1;
rect_dsc.bg_grad.stops[0].color = lv_color_white();
rect_dsc.bg_grad.stops[1].color = lv_color_black();
lv_draw_rect(&layer, &rect_dsc, &a);
lv_canvas_finish_layer(canvas, &layer);
/*Comment it to make the mask visible*/
lv_obj_delete(canvas);
}
/**
* Add a fade mask to roller.
*/
void lv_example_roller_3(void)
{
lv_obj_set_style_bg_color(lv_screen_active(), lv_palette_main(LV_PALETTE_BLUE_GREY), 0);
static lv_style_t style;
lv_style_init(&style);
lv_style_set_bg_color(&style, lv_color_black());
lv_style_set_text_color(&style, lv_color_white());
lv_style_set_border_width(&style, 0);
lv_style_set_radius(&style, 0);
lv_obj_t * roller1 = lv_roller_create(lv_screen_active());
lv_obj_add_style(roller1, &style, 0);
lv_obj_set_style_bg_opa(roller1, LV_OPA_50, LV_PART_SELECTED);
lv_roller_set_options(roller1,
"January\n"
"February\n"
"March\n"
"April\n"
"May\n"
"June\n"
"July\n"
"August\n"
"September\n"
"October\n"
"November\n"
"December",
LV_ROLLER_MODE_NORMAL);
lv_obj_center(roller1);
lv_roller_set_visible_row_count(roller1, 4);
/* Create the mask to make the top and bottom part of roller faded.
* The width and height are empirical values for simplicity*/
LV_DRAW_BUF_DEFINE_STATIC(mask, 130, 150, LV_COLOR_FORMAT_L8);
LV_DRAW_BUF_INIT_STATIC(mask);
generate_mask(&mask);
lv_obj_set_style_bitmap_mask_src(roller1, &mask, 0);
}
#endif
Scale（标尺）
A simple horizontal scale
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_SCALE && LV_BUILD_EXAMPLES
/**
* A simple horizontal scale
*/
void lv_example_scale_1(void)
{
lv_obj_t * scale = lv_scale_create(lv_screen_active());
lv_obj_set_size(scale, lv_pct(80), 100);
lv_scale_set_mode(scale, LV_SCALE_MODE_HORIZONTAL_BOTTOM);
lv_obj_center(scale);
lv_scale_set_label_show(scale, true);
lv_scale_set_total_tick_count(scale, 31);
lv_scale_set_major_tick_every(scale, 5);
lv_obj_set_style_length(scale, 5, LV_PART_ITEMS);
lv_obj_set_style_length(scale, 10, LV_PART_INDICATOR);
lv_scale_set_range(scale, 10, 40);
}
#endif
An vertical scale with section and custom styling
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_SCALE && LV_BUILD_EXAMPLES
/**
* An vertical scale with section and custom styling
*/
void lv_example_scale_2(void)
{
lv_obj_t * scale = lv_scale_create(lv_screen_active());
lv_obj_set_size(scale, 60, 200);
lv_scale_set_label_show(scale, true);
lv_scale_set_mode(scale, LV_SCALE_MODE_VERTICAL_RIGHT);
lv_obj_center(scale);
lv_scale_set_total_tick_count(scale, 21);
lv_scale_set_major_tick_every(scale, 5);
lv_obj_set_style_length(scale, 10, LV_PART_INDICATOR);
lv_obj_set_style_length(scale, 5, LV_PART_ITEMS);
lv_scale_set_range(scale, 0, 100);
static const char * custom_labels[] = {"0 °C", "25 °C", "50 °C", "75 °C", "100 °C", NULL};
lv_scale_set_text_src(scale, custom_labels);
static lv_style_t indicator_style;
lv_style_init(&indicator_style);
/* Label style properties */
lv_style_set_text_font(&indicator_style, LV_FONT_DEFAULT);
lv_style_set_text_color(&indicator_style, lv_palette_darken(LV_PALETTE_BLUE, 3));
/* Major tick properties */
lv_style_set_line_color(&indicator_style, lv_palette_darken(LV_PALETTE_BLUE, 3));
lv_style_set_width(&indicator_style, 10U); /*Tick length*/
lv_style_set_line_width(&indicator_style, 2U); /*Tick width*/
lv_obj_add_style(scale, &indicator_style, LV_PART_INDICATOR);
static lv_style_t minor_ticks_style;
lv_style_init(&minor_ticks_style);
lv_style_set_line_color(&minor_ticks_style, lv_palette_lighten(LV_PALETTE_BLUE, 2));
lv_style_set_width(&minor_ticks_style, 5U); /*Tick length*/
lv_style_set_line_width(&minor_ticks_style, 2U); /*Tick width*/
lv_obj_add_style(scale, &minor_ticks_style, LV_PART_ITEMS);
static lv_style_t main_line_style;
lv_style_init(&main_line_style);
/* Main line properties */
lv_style_set_line_color(&main_line_style, lv_palette_darken(LV_PALETTE_BLUE, 3));
lv_style_set_line_width(&main_line_style, 2U); // Tick width
lv_obj_add_style(scale, &main_line_style, LV_PART_MAIN);
/* Add a section */
static lv_style_t section_minor_tick_style;
static lv_style_t section_label_style;
static lv_style_t section_main_line_style;
lv_style_init(§ion_label_style);
lv_style_init(§ion_minor_tick_style);
lv_style_init(§ion_main_line_style);
/* Label style properties */
lv_style_set_text_font(§ion_label_style, LV_FONT_DEFAULT);
lv_style_set_text_color(§ion_label_style, lv_palette_darken(LV_PALETTE_RED, 3));
lv_style_set_line_color(§ion_label_style, lv_palette_darken(LV_PALETTE_RED, 3));
lv_style_set_line_width(§ion_label_style, 5U); /*Tick width*/
lv_style_set_line_color(§ion_minor_tick_style, lv_palette_lighten(LV_PALETTE_RED, 2));
lv_style_set_line_width(§ion_minor_tick_style, 4U); /*Tick width*/
/* Main line properties */
lv_style_set_line_color(§ion_main_line_style, lv_palette_darken(LV_PALETTE_RED, 3));
lv_style_set_line_width(§ion_main_line_style, 4U); /*Tick width*/
/* Configure section styles */
lv_scale_section_t * section = lv_scale_add_section(scale);
lv_scale_section_set_range(section, 75, 100);
lv_scale_section_set_style(section, LV_PART_INDICATOR, §ion_label_style);
lv_scale_section_set_style(section, LV_PART_ITEMS, §ion_minor_tick_style);
lv_scale_section_set_style(section, LV_PART_MAIN, §ion_main_line_style);
lv_obj_set_style_bg_color(scale, lv_palette_main(LV_PALETTE_BLUE_GREY), 0);
lv_obj_set_style_bg_opa(scale, LV_OPA_50, 0);
lv_obj_set_style_pad_left(scale, 8, 0);
lv_obj_set_style_radius(scale, 8, 0);
lv_obj_set_style_pad_ver(scale, 20, 0);
}
#endif
A simple round scale
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_SCALE && LV_BUILD_EXAMPLES
LV_IMAGE_DECLARE(img_hand);
lv_obj_t * needle_line;
lv_obj_t * needle_img;
static void set_needle_line_value(void * obj, int32_t v)
{
lv_scale_set_line_needle_value(obj, needle_line, 60, v);
}
static void set_needle_img_value(void * obj, int32_t v)
{
lv_scale_set_image_needle_value(obj, needle_img, v);
}
/**
* A simple round scale
*/
void lv_example_scale_3(void)
{
lv_obj_t * scale_line = lv_scale_create(lv_screen_active());
lv_obj_set_size(scale_line, 150, 150);
lv_scale_set_mode(scale_line, LV_SCALE_MODE_ROUND_INNER);
lv_obj_set_style_bg_opa(scale_line, LV_OPA_COVER, 0);
lv_obj_set_style_bg_color(scale_line, lv_palette_lighten(LV_PALETTE_RED, 5), 0);
lv_obj_set_style_radius(scale_line, LV_RADIUS_CIRCLE, 0);
lv_obj_set_style_clip_corner(scale_line, true, 0);
lv_obj_align(scale_line, LV_ALIGN_LEFT_MID, LV_PCT(2), 0);
lv_scale_set_label_show(scale_line, true);
lv_scale_set_total_tick_count(scale_line, 31);
lv_scale_set_major_tick_every(scale_line, 5);
lv_obj_set_style_length(scale_line, 5, LV_PART_ITEMS);
lv_obj_set_style_length(scale_line, 10, LV_PART_INDICATOR);
lv_scale_set_range(scale_line, 10, 40);
lv_scale_set_angle_range(scale_line, 270);
lv_scale_set_rotation(scale_line, 135);
needle_line = lv_line_create(scale_line);
lv_obj_set_style_line_width(needle_line, 6, LV_PART_MAIN);
lv_obj_set_style_line_rounded(needle_line, true, LV_PART_MAIN);
lv_anim_t anim_scale_line;
lv_anim_init(&anim_scale_line);
lv_anim_set_var(&anim_scale_line, scale_line);
lv_anim_set_exec_cb(&anim_scale_line, set_needle_line_value);
lv_anim_set_duration(&anim_scale_line, 1000);
lv_anim_set_repeat_count(&anim_scale_line, LV_ANIM_REPEAT_INFINITE);
lv_anim_set_playback_duration(&anim_scale_line, 1000);
lv_anim_set_values(&anim_scale_line, 10, 40);
lv_anim_start(&anim_scale_line);
lv_obj_t * scale_img = lv_scale_create(lv_screen_active());
lv_obj_set_size(scale_img, 150, 150);
lv_scale_set_mode(scale_img, LV_SCALE_MODE_ROUND_INNER);
lv_obj_set_style_bg_opa(scale_img, LV_OPA_COVER, 0);
lv_obj_set_style_bg_color(scale_img, lv_palette_lighten(LV_PALETTE_RED, 5), 0);
lv_obj_set_style_radius(scale_img, LV_RADIUS_CIRCLE, 0);
lv_obj_set_style_clip_corner(scale_img, true, 0);
lv_obj_align(scale_img, LV_ALIGN_RIGHT_MID, LV_PCT(-2), 0);
lv_scale_set_label_show(scale_img, true);
lv_scale_set_total_tick_count(scale_img, 31);
lv_scale_set_major_tick_every(scale_img, 5);
lv_obj_set_style_length(scale_img, 5, LV_PART_ITEMS);
lv_obj_set_style_length(scale_img, 10, LV_PART_INDICATOR);
lv_scale_set_range(scale_img, 10, 40);
lv_scale_set_angle_range(scale_img, 270);
lv_scale_set_rotation(scale_img, 135);
/* image must point to the right. E.g. -O------>*/
needle_img = lv_image_create(scale_img);
lv_image_set_src(needle_img, &img_hand);
lv_obj_align(needle_img, LV_ALIGN_CENTER, 47, -2);
lv_image_set_pivot(needle_img, 3, 4);
lv_anim_t anim_scale_img;
lv_anim_init(&anim_scale_img);
lv_anim_set_var(&anim_scale_img, scale_img);
lv_anim_set_exec_cb(&anim_scale_img, set_needle_img_value);
lv_anim_set_duration(&anim_scale_img, 1000);
lv_anim_set_repeat_count(&anim_scale_img, LV_ANIM_REPEAT_INFINITE);
lv_anim_set_playback_duration(&anim_scale_img, 1000);
lv_anim_set_values(&anim_scale_img, 10, 40);
lv_anim_start(&anim_scale_img);
}
#endif
A round scale with section and custom styling
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_SCALE && LV_BUILD_EXAMPLES
/**
* A round scale with section and custom styling
*/
void lv_example_scale_4(void)
{
lv_obj_t * scale = lv_scale_create(lv_screen_active());
lv_obj_set_size(scale, 150, 150);
lv_scale_set_label_show(scale, true);
lv_scale_set_mode(scale, LV_SCALE_MODE_ROUND_OUTER);
lv_obj_center(scale);
lv_scale_set_total_tick_count(scale, 21);
lv_scale_set_major_tick_every(scale, 5);
lv_obj_set_style_length(scale, 5, LV_PART_ITEMS);
lv_obj_set_style_length(scale, 10, LV_PART_INDICATOR);
lv_scale_set_range(scale, 0, 100);
static const char * custom_labels[] = {"0 °C", "25 °C", "50 °C", "75 °C", "100 °C", NULL};
lv_scale_set_text_src(scale, custom_labels);
static lv_style_t indicator_style;
lv_style_init(&indicator_style);
/* Label style properties */
lv_style_set_text_font(&indicator_style, LV_FONT_DEFAULT);
lv_style_set_text_color(&indicator_style, lv_palette_darken(LV_PALETTE_BLUE, 3));
/* Major tick properties */
lv_style_set_line_color(&indicator_style, lv_palette_darken(LV_PALETTE_BLUE, 3));
lv_style_set_width(&indicator_style, 10U); /*Tick length*/
lv_style_set_line_width(&indicator_style, 2U); /*Tick width*/
lv_obj_add_style(scale, &indicator_style, LV_PART_INDICATOR);
static lv_style_t minor_ticks_style;
lv_style_init(&minor_ticks_style);
lv_style_set_line_color(&minor_ticks_style, lv_palette_lighten(LV_PALETTE_BLUE, 2));
lv_style_set_width(&minor_ticks_style, 5U); /*Tick length*/
lv_style_set_line_width(&minor_ticks_style, 2U); /*Tick width*/
lv_obj_add_style(scale, &minor_ticks_style, LV_PART_ITEMS);
static lv_style_t main_line_style;
lv_style_init(&main_line_style);
/* Main line properties */
lv_style_set_arc_color(&main_line_style, lv_palette_darken(LV_PALETTE_BLUE, 3));
lv_style_set_arc_width(&main_line_style, 2U); /*Tick width*/
lv_obj_add_style(scale, &main_line_style, LV_PART_MAIN);
/* Add a section */
static lv_style_t section_minor_tick_style;
static lv_style_t section_label_style;
static lv_style_t section_main_line_style;
lv_style_init(§ion_label_style);
lv_style_init(§ion_minor_tick_style);
lv_style_init(§ion_main_line_style);
/* Label style properties */
lv_style_set_text_font(§ion_label_style, LV_FONT_DEFAULT);
lv_style_set_text_color(§ion_label_style, lv_palette_darken(LV_PALETTE_RED, 3));
lv_style_set_line_color(§ion_label_style, lv_palette_darken(LV_PALETTE_RED, 3));
lv_style_set_line_width(§ion_label_style, 5U); /*Tick width*/
lv_style_set_line_color(§ion_minor_tick_style, lv_palette_lighten(LV_PALETTE_RED, 2));
lv_style_set_line_width(§ion_minor_tick_style, 4U); /*Tick width*/
/* Main line properties */
lv_style_set_arc_color(§ion_main_line_style, lv_palette_darken(LV_PALETTE_RED, 3));
lv_style_set_arc_width(§ion_main_line_style, 4U); /*Tick width*/
/* Configure section styles */
lv_scale_section_t * section = lv_scale_add_section(scale);
lv_scale_section_set_range(section, 75, 100);
lv_scale_section_set_style(section, LV_PART_INDICATOR, §ion_label_style);
lv_scale_section_set_style(section, LV_PART_ITEMS, §ion_minor_tick_style);
lv_scale_section_set_style(section, LV_PART_MAIN, §ion_main_line_style);
}
#endif
A round scale with section and custom styling
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_SCALE && LV_BUILD_EXAMPLES
/**
* An scale with section and custom styling
*/
void lv_example_scale_5(void)
{
lv_obj_t * scale = lv_scale_create(lv_screen_active());
lv_obj_set_size(scale, lv_display_get_horizontal_resolution(NULL) / 2, lv_display_get_vertical_resolution(NULL) / 2);
lv_scale_set_label_show(scale, true);
lv_scale_set_total_tick_count(scale, 10);
lv_scale_set_major_tick_every(scale, 5);
lv_obj_set_style_length(scale, 5, LV_PART_ITEMS);
lv_obj_set_style_length(scale, 10, LV_PART_INDICATOR);
lv_scale_set_range(scale, 25, 35);
static const char * custom_labels[3] = {"One", "Two", NULL};
lv_scale_set_text_src(scale, custom_labels);
static lv_style_t indicator_style;
lv_style_init(&indicator_style);
/* Label style properties */
lv_style_set_text_font(&indicator_style, LV_FONT_DEFAULT);
lv_style_set_text_color(&indicator_style, lv_color_hex(0xff00ff));
/* Major tick properties */
lv_style_set_line_color(&indicator_style, lv_color_hex(0x00ff00));
lv_style_set_width(&indicator_style, 10U); // Tick length
lv_style_set_line_width(&indicator_style, 2U); // Tick width
lv_obj_add_style(scale, &indicator_style, LV_PART_INDICATOR);
static lv_style_t minor_ticks_style;
lv_style_init(&minor_ticks_style);
lv_style_set_line_color(&minor_ticks_style, lv_color_hex(0xff0000));
lv_style_set_width(&minor_ticks_style, 5U); // Tick length
lv_style_set_line_width(&minor_ticks_style, 2U); // Tick width
lv_obj_add_style(scale, &minor_ticks_style, LV_PART_ITEMS);
static lv_style_t main_line_style;
lv_style_init(&main_line_style);
/* Main line properties */
lv_style_set_line_color(&main_line_style, lv_color_hex(0x0000ff));
lv_style_set_line_width(&main_line_style, 2U); // Tick width
lv_obj_add_style(scale, &main_line_style, LV_PART_MAIN);
lv_obj_center(scale);
/* Add a section */
static lv_style_t section_minor_tick_style;
static lv_style_t section_label_style;
lv_style_init(§ion_label_style);
lv_style_init(§ion_minor_tick_style);
/* Label style properties */
lv_style_set_text_font(§ion_label_style, LV_FONT_DEFAULT);
lv_style_set_text_color(§ion_label_style, lv_color_hex(0xff0000));
lv_style_set_text_letter_space(§ion_label_style, 10);
lv_style_set_text_opa(§ion_label_style, LV_OPA_50);
lv_style_set_line_color(§ion_label_style, lv_color_hex(0xff0000));
// lv_style_set_width(§ion_label_style, 20U); // Tick length
lv_style_set_line_width(§ion_label_style, 5U); // Tick width
lv_style_set_line_color(§ion_minor_tick_style, lv_color_hex(0x0000ff));
// lv_style_set_width(§ion_label_style, 20U); // Tick length
lv_style_set_line_width(§ion_minor_tick_style, 4U); // Tick width
/* Configure section styles */
lv_scale_section_t * section = lv_scale_add_section(scale);
lv_scale_section_set_range(section, 25, 30);
lv_scale_section_set_style(section, LV_PART_INDICATOR, §ion_label_style);
lv_scale_section_set_style(section, LV_PART_ITEMS, §ion_minor_tick_style);
}
#endif
A round scale with multiple needles, resembling a clock
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_SCALE && LV_BUILD_EXAMPLES
#if LV_USE_FLOAT
#define my_PRIprecise "f"
#else
#define my_PRIprecise LV_PRId32
#endif
static lv_obj_t * scale;
static lv_obj_t * minute_hand;
static lv_obj_t * hour_hand;
static lv_point_precise_t minute_hand_points[2];
static int32_t hour;
static int32_t minute;
static void timer_cb(lv_timer_t * timer)
{
LV_UNUSED(timer);
minute++;
if(minute > 59) {
minute = 0;
hour++;
if(hour > 11) {
hour = 0;
}
}
/**
* the scale will store the needle line points in the existing
* point array if one was set with `lv_line_set_points_mutable`.
* Otherwise, it will allocate the needle line points.
*/
/* the scale will store the minute hand line points in `minute_hand_points` */
lv_scale_set_line_needle_value(scale, minute_hand, 60, minute);
/* log the points that were stored in the array */
LV_LOG_USER(
"minute hand points - "
"0: (%" my_PRIprecise ", %" my_PRIprecise "), "
"1: (%" my_PRIprecise ", %" my_PRIprecise ")",
minute_hand_points[0].x, minute_hand_points[0].y,
minute_hand_points[1].x, minute_hand_points[1].y
);
/* the scale will allocate the hour hand line points */
lv_scale_set_line_needle_value(scale, hour_hand, 40, hour * 5 + (minute / 12));
}
/**
* A round scale with multiple needles, resembling a clock
*/
void lv_example_scale_6(void)
{
scale = lv_scale_create(lv_screen_active());
lv_obj_set_size(scale, 150, 150);
lv_scale_set_mode(scale, LV_SCALE_MODE_ROUND_INNER);
lv_obj_set_style_bg_opa(scale, LV_OPA_60, 0);
lv_obj_set_style_bg_color(scale, lv_color_black(), 0);
lv_obj_set_style_radius(scale, LV_RADIUS_CIRCLE, 0);
lv_obj_set_style_clip_corner(scale, true, 0);
lv_obj_center(scale);
lv_scale_set_label_show(scale, true);
lv_scale_set_total_tick_count(scale, 61);
lv_scale_set_major_tick_every(scale, 5);
static const char * hour_ticks[] = {"12", "1", "2", "3", "4", "5", "6", "7", "8", "9", "10", "11", NULL};
lv_scale_set_text_src(scale, hour_ticks);
static lv_style_t indicator_style;
lv_style_init(&indicator_style);
/* Label style properties */
lv_style_set_text_font(&indicator_style, LV_FONT_DEFAULT);
lv_style_set_text_color(&indicator_style, lv_palette_main(LV_PALETTE_YELLOW));
/* Major tick properties */
lv_style_set_line_color(&indicator_style, lv_palette_main(LV_PALETTE_YELLOW));
lv_style_set_length(&indicator_style, 8); /* tick length */
lv_style_set_line_width(&indicator_style, 2); /* tick width */
lv_obj_add_style(scale, &indicator_style, LV_PART_INDICATOR);
/* Minor tick properties */
static lv_style_t minor_ticks_style;
lv_style_init(&minor_ticks_style);
lv_style_set_line_color(&minor_ticks_style, lv_palette_main(LV_PALETTE_YELLOW));
lv_style_set_length(&minor_ticks_style, 6); /* tick length */
lv_style_set_line_width(&minor_ticks_style, 2); /* tick width */
lv_obj_add_style(scale, &minor_ticks_style, LV_PART_ITEMS);
/* Main line properties */
static lv_style_t main_line_style;
lv_style_init(&main_line_style);
lv_style_set_arc_color(&main_line_style, lv_color_black());
lv_style_set_arc_width(&main_line_style, 5);
lv_obj_add_style(scale, &main_line_style, LV_PART_MAIN);
lv_scale_set_range(scale, 0, 60);
lv_scale_set_angle_range(scale, 360);
lv_scale_set_rotation(scale, 270);
minute_hand = lv_line_create(scale);
lv_line_set_points_mutable(minute_hand, minute_hand_points, 2);
lv_obj_set_style_line_width(minute_hand, 3, 0);
lv_obj_set_style_line_rounded(minute_hand, true, 0);
lv_obj_set_style_line_color(minute_hand, lv_color_white(), 0);
hour_hand = lv_line_create(scale);
lv_obj_set_style_line_width(hour_hand, 5, 0);
lv_obj_set_style_line_rounded(hour_hand, true, 0);
lv_obj_set_style_line_color(hour_hand, lv_palette_main(LV_PALETTE_RED), 0);
hour = 11;
minute = 5;
lv_timer_t * timer = lv_timer_create(timer_cb, 250, NULL);
lv_timer_ready(timer);
}
#endif
A round scale with multiple needles, resembling a clock
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_SCALE && LV_BUILD_EXAMPLES
#include "../../../src/lvgl_private.h" //To expose the fields of lv_draw_task_t
static void draw_event_cb(lv_event_t * e)
{
lv_obj_t * obj = lv_event_get_target(e);
lv_draw_task_t * draw_task = lv_event_get_draw_task(e);
lv_draw_dsc_base_t * base_dsc = lv_draw_task_get_draw_dsc(draw_task);
lv_draw_label_dsc_t * label_draw_dsc = lv_draw_task_get_label_dsc(draw_task);
if(base_dsc->part == LV_PART_INDICATOR) {
if(label_draw_dsc) {
const lv_color_t color_idx[7] = {
lv_palette_main(LV_PALETTE_RED),
lv_palette_main(LV_PALETTE_ORANGE),
lv_palette_main(LV_PALETTE_YELLOW),
lv_palette_main(LV_PALETTE_GREEN),
lv_palette_main(LV_PALETTE_CYAN),
lv_palette_main(LV_PALETTE_BLUE),
lv_palette_main(LV_PALETTE_PURPLE),
};
uint8_t major_tick = lv_scale_get_major_tick_every(obj);
label_draw_dsc->color = color_idx[base_dsc->id1 / major_tick];
/*Free the previously allocated text if needed*/
if(label_draw_dsc->text_local) lv_free((void *)label_draw_dsc->text);
/*Malloc the text and set text_local as 1 to make LVGL automatically free the text.
* (Local texts are malloc'd internally by LVGL. Mimic this behavior here too)*/
char tmp_buffer[20] = {0}; /* Big enough buffer */
lv_snprintf(tmp_buffer, sizeof(tmp_buffer), "%.1f", base_dsc->id2 * 1.0f);
label_draw_dsc->text = lv_strdup(tmp_buffer);
label_draw_dsc->text_local = 1;
lv_point_t size;
lv_text_get_size(&size, label_draw_dsc->text, label_draw_dsc->font, 0, 0, 1000, LV_TEXT_FLAG_NONE);
int32_t new_w = size.x;
int32_t old_w = lv_area_get_width(&draw_task->area);
/* Distribute the new size equally on both sides */
draw_task->area.x1 -= (new_w - old_w) / 2;
draw_task->area.x2 += ((new_w - old_w) + 1) / 2; /* +1 for rounding */
}
}
}
/**
* Customizing scale major tick label color with `LV_EVENT_DRAW_TASK_ADDED` event
*/
void lv_example_scale_7(void)
{
lv_obj_t * scale = lv_scale_create(lv_screen_active());
lv_obj_set_size(scale, lv_pct(80), 100);
lv_scale_set_mode(scale, LV_SCALE_MODE_HORIZONTAL_BOTTOM);
lv_obj_center(scale);
lv_scale_set_label_show(scale, true);
lv_scale_set_total_tick_count(scale, 31);
lv_scale_set_major_tick_every(scale, 5);
lv_obj_set_style_length(scale, 5, LV_PART_ITEMS);
lv_obj_set_style_length(scale, 10, LV_PART_INDICATOR);
lv_scale_set_range(scale, 10, 40);
lv_obj_add_event_cb(scale, draw_event_cb, LV_EVENT_DRAW_TASK_ADDED, NULL);
lv_obj_add_flag(scale, LV_OBJ_FLAG_SEND_DRAW_TASK_EVENTS);
}
#endif
A round scale with multiple needles, resembling a clock
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_SCALE && LV_BUILD_EXAMPLES
/**
* A simple round scale with label/tick translation
*/
void lv_example_scale_8(void)
{
lv_obj_t * scale_line = lv_scale_create(lv_screen_active());
lv_obj_set_size(scale_line, 150, 150);
lv_scale_set_mode(scale_line, LV_SCALE_MODE_ROUND_INNER);
lv_obj_set_style_bg_opa(scale_line, LV_OPA_COVER, 0);
lv_obj_set_style_bg_color(scale_line, lv_palette_lighten(LV_PALETTE_RED, 5), 0);
lv_obj_set_style_radius(scale_line, LV_RADIUS_CIRCLE, 0);
lv_obj_align(scale_line, LV_ALIGN_LEFT_MID, LV_PCT(2), 0);
/*Set the texts' and major ticks' style (make the texts rotated)*/
lv_obj_set_style_transform_rotation(scale_line, LV_SCALE_LABEL_ROTATE_MATCH_TICKS | LV_SCALE_LABEL_ROTATE_KEEP_UPRIGHT,
LV_PART_INDICATOR);
lv_obj_set_style_translate_x(scale_line, 10, LV_PART_INDICATOR);
lv_obj_set_style_length(scale_line, 15, LV_PART_INDICATOR);
lv_obj_set_style_radial_offset(scale_line, 10, LV_PART_INDICATOR);
/*Set the style of the minor ticks*/
lv_obj_set_style_length(scale_line, 10, LV_PART_ITEMS);
lv_obj_set_style_radial_offset(scale_line, 5, LV_PART_ITEMS);
lv_obj_set_style_line_opa(scale_line, LV_OPA_50, LV_PART_ITEMS);
lv_scale_set_label_show(scale_line, true);
lv_scale_set_total_tick_count(scale_line, 31);
lv_scale_set_major_tick_every(scale_line, 5);
lv_scale_set_range(scale_line, 10, 40);
lv_scale_set_angle_range(scale_line, 270);
lv_scale_set_rotation(scale_line, 135);
lv_obj_t * needle_line = lv_line_create(scale_line);
lv_obj_set_style_line_width(needle_line, 3, LV_PART_MAIN);
lv_obj_set_style_line_rounded(needle_line, true, LV_PART_MAIN);
lv_scale_set_line_needle_value(scale_line, needle_line, 60, 33);
}
#endif
A round scale with multiple needles, resembling a clock
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_SCALE && LV_BUILD_EXAMPLES
/**
* A simple horizontal scale with transforms
*/
void lv_example_scale_9(void)
{
lv_obj_t * scale = lv_scale_create(lv_screen_active());
lv_obj_set_size(scale, 200, 100);
lv_scale_set_mode(scale, LV_SCALE_MODE_HORIZONTAL_BOTTOM);
lv_obj_center(scale);
lv_scale_set_label_show(scale, true);
lv_obj_set_style_transform_rotation(scale, 450, LV_PART_INDICATOR);
lv_obj_set_style_length(scale, 30, LV_PART_INDICATOR);
lv_obj_set_style_translate_x(scale, 5, LV_PART_INDICATOR);
lv_scale_set_total_tick_count(scale, 31);
lv_scale_set_major_tick_every(scale, 5);
lv_obj_set_style_length(scale, 5, LV_PART_ITEMS);
lv_obj_set_style_length(scale, 10, LV_PART_INDICATOR);
lv_scale_set_range(scale, 10, 40);
}
#endif
Slider（滑动条）
Simple Slider
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_SLIDER && LV_BUILD_EXAMPLES
static void slider_event_cb(lv_event_t * e);
static lv_obj_t * slider_label;
/**
* A default slider with a label displaying the current value
*/
void lv_example_slider_1(void)
{
/*Create a slider in the center of the display*/
lv_obj_t * slider = lv_slider_create(lv_screen_active());
lv_obj_center(slider);
lv_obj_add_event_cb(slider, slider_event_cb, LV_EVENT_VALUE_CHANGED, NULL);
lv_obj_set_style_anim_duration(slider, 2000, 0);
/*Create a label below the slider*/
slider_label = lv_label_create(lv_screen_active());
lv_label_set_text(slider_label, "0%");
lv_obj_align_to(slider_label, slider, LV_ALIGN_OUT_BOTTOM_MID, 0, 10);
}
static void slider_event_cb(lv_event_t * e)
{
lv_obj_t * slider = lv_event_get_target(e);
char buf[8];
lv_snprintf(buf, sizeof(buf), "%d%%", (int)lv_slider_get_value(slider));
lv_label_set_text(slider_label, buf);
lv_obj_align_to(slider_label, slider, LV_ALIGN_OUT_BOTTOM_MID, 0, 10);
}
#endif
Slider with custom style
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_SLIDER && LV_BUILD_EXAMPLES
/**
* Show how to style a slider.
*/
void lv_example_slider_2(void)
{
/*Create a transition*/
static const lv_style_prop_t props[] = {LV_STYLE_BG_COLOR, 0};
static lv_style_transition_dsc_t transition_dsc;
lv_style_transition_dsc_init(&transition_dsc, props, lv_anim_path_linear, 300, 0, NULL);
static lv_style_t style_main;
static lv_style_t style_indicator;
static lv_style_t style_knob;
static lv_style_t style_pressed_color;
lv_style_init(&style_main);
lv_style_set_bg_opa(&style_main, LV_OPA_COVER);
lv_style_set_bg_color(&style_main, lv_color_hex3(0xbbb));
lv_style_set_radius(&style_main, LV_RADIUS_CIRCLE);
lv_style_set_pad_ver(&style_main, -2); /*Makes the indicator larger*/
lv_style_init(&style_indicator);
lv_style_set_bg_opa(&style_indicator, LV_OPA_COVER);
lv_style_set_bg_color(&style_indicator, lv_palette_main(LV_PALETTE_CYAN));
lv_style_set_radius(&style_indicator, LV_RADIUS_CIRCLE);
lv_style_set_transition(&style_indicator, &transition_dsc);
lv_style_init(&style_knob);
lv_style_set_bg_opa(&style_knob, LV_OPA_COVER);
lv_style_set_bg_color(&style_knob, lv_palette_main(LV_PALETTE_CYAN));
lv_style_set_border_color(&style_knob, lv_palette_darken(LV_PALETTE_CYAN, 3));
lv_style_set_border_width(&style_knob, 2);
lv_style_set_radius(&style_knob, LV_RADIUS_CIRCLE);
lv_style_set_pad_all(&style_knob, 6); /*Makes the knob larger*/
lv_style_set_transition(&style_knob, &transition_dsc);
lv_style_init(&style_pressed_color);
lv_style_set_bg_color(&style_pressed_color, lv_palette_darken(LV_PALETTE_CYAN, 2));
/*Create a slider and add the style*/
lv_obj_t * slider = lv_slider_create(lv_screen_active());
lv_obj_remove_style_all(slider); /*Remove the styles coming from the theme*/
lv_obj_add_style(slider, &style_main, LV_PART_MAIN);
lv_obj_add_style(slider, &style_indicator, LV_PART_INDICATOR);
lv_obj_add_style(slider, &style_pressed_color, LV_PART_INDICATOR | LV_STATE_PRESSED);
lv_obj_add_style(slider, &style_knob, LV_PART_KNOB);
lv_obj_add_style(slider, &style_pressed_color, LV_PART_KNOB | LV_STATE_PRESSED);
lv_obj_center(slider);
}
#endif
Slider with extended drawer
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_SLIDER && LV_BUILD_EXAMPLES
#define MAX_VALUE 100
#define MIN_VALUE 0
static void slider_event_cb(lv_event_t * e);
/**
* Show the current value when the slider is pressed by extending the drawer
*
*/
void lv_example_slider_3(void)
{
/*Create a slider in the center of the display*/
lv_obj_t * slider;
slider = lv_slider_create(lv_screen_active());
lv_obj_center(slider);
lv_slider_set_mode(slider, LV_SLIDER_MODE_RANGE);
lv_slider_set_range(slider, MIN_VALUE, MAX_VALUE);
lv_slider_set_value(slider, 70, LV_ANIM_OFF);
lv_slider_set_left_value(slider, 20, LV_ANIM_OFF);
lv_obj_add_event_cb(slider, slider_event_cb, LV_EVENT_ALL, NULL);
lv_obj_refresh_ext_draw_size(slider);
}
static void slider_event_cb(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * obj = lv_event_get_target(e);
/*Provide some extra space for the value*/
if(code == LV_EVENT_REFR_EXT_DRAW_SIZE) {
lv_event_set_ext_draw_size(e, 50);
}
else if(code == LV_EVENT_DRAW_MAIN_END) {
if(!lv_obj_has_state(obj, LV_STATE_PRESSED)) return;
lv_area_t slider_area;
lv_obj_get_coords(obj, &slider_area);
lv_area_t indic_area = slider_area;
lv_area_set_width(&indic_area, lv_area_get_width(&slider_area) * lv_slider_get_value(obj) / MAX_VALUE);
indic_area.x1 += lv_area_get_width(&slider_area) * lv_slider_get_left_value(obj) / MAX_VALUE;
char buf[16];
lv_snprintf(buf, sizeof(buf), "%d - %d", (int)lv_slider_get_left_value(obj), (int)lv_slider_get_value(obj));
lv_point_t label_size;
lv_text_get_size(&label_size, buf, LV_FONT_DEFAULT, 0, 0, LV_COORD_MAX, 0);
lv_area_t label_area;
label_area.x1 = 0;
label_area.x2 = label_size.x - 1;
label_area.y1 = 0;
label_area.y2 = label_size.y - 1;
lv_area_align(&indic_area, &label_area, LV_ALIGN_OUT_TOP_MID, 0, -10);
lv_draw_label_dsc_t label_draw_dsc;
lv_draw_label_dsc_init(&label_draw_dsc);
label_draw_dsc.color = lv_color_hex3(0x888);
label_draw_dsc.text = buf;
label_draw_dsc.text_local = true;
lv_layer_t * layer = lv_event_get_layer(e);
lv_draw_label(layer, &label_draw_dsc, &label_area);
}
}
#endif
Slider with opposite direction
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_SLIDER && LV_BUILD_EXAMPLES
static void slider_event_cb(lv_event_t * e);
static lv_obj_t * slider_label;
/**
* Slider with opposite direction
*/
void lv_example_slider_4(void)
{
/*Create a slider in the center of the display*/
lv_obj_t * slider = lv_slider_create(lv_screen_active());
lv_obj_center(slider);
lv_obj_add_event_cb(slider, slider_event_cb, LV_EVENT_VALUE_CHANGED, NULL);
/*Reverse the direction of the slider*/
lv_slider_set_range(slider, 100, 0);
/*Create a label below the slider*/
slider_label = lv_label_create(lv_screen_active());
lv_label_set_text(slider_label, "0%");
lv_obj_align_to(slider_label, slider, LV_ALIGN_OUT_BOTTOM_MID, 0, 10);
}
static void slider_event_cb(lv_event_t * e)
{
lv_obj_t * slider = lv_event_get_target(e);
char buf[8];
lv_snprintf(buf, sizeof(buf), "%d%%", (int)lv_slider_get_value(slider));
lv_label_set_text(slider_label, buf);
lv_obj_align_to(slider_label, slider, LV_ALIGN_OUT_BOTTOM_MID, 0, 10);
}
#endif
Span（富文本）
Span with custom styles
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_SPAN && LV_BUILD_EXAMPLES
static void click_event_cb(lv_event_t * e)
{
lv_obj_t * spans = lv_event_get_target(e);
lv_indev_t * indev = lv_event_get_indev(e);
lv_point_t point;
lv_indev_get_point(indev, &point);
lv_span_t * span = lv_spangroup_get_span_by_point(spans, &point);
LV_LOG_USER("%s", span ? lv_span_get_text(span) : "NULL");
}
/**
* Create spans and get clicked one
*/
void lv_example_span_1(void)
{
static lv_style_t style;
lv_style_init(&style);
lv_style_set_border_width(&style, 1);
lv_style_set_border_color(&style, lv_palette_main(LV_PALETTE_ORANGE));
lv_style_set_pad_all(&style, 2);
lv_obj_t * spans = lv_spangroup_create(lv_screen_active());
lv_obj_set_width(spans, 300);
lv_obj_set_height(spans, 300);
lv_obj_center(spans);
lv_obj_add_style(spans, &style, 0);
lv_obj_add_flag(spans, LV_OBJ_FLAG_CLICKABLE);
lv_spangroup_set_align(spans, LV_TEXT_ALIGN_LEFT);
lv_spangroup_set_overflow(spans, LV_SPAN_OVERFLOW_CLIP);
lv_spangroup_set_indent(spans, 20);
lv_spangroup_set_mode(spans, LV_SPAN_MODE_BREAK);
lv_span_t * span = lv_spangroup_new_span(spans);
lv_span_set_text(span, "China is a beautiful country.");
lv_style_set_text_color(lv_span_get_style(span), lv_palette_main(LV_PALETTE_RED));
lv_style_set_text_decor(lv_span_get_style(span), LV_TEXT_DECOR_UNDERLINE);
lv_style_set_text_opa(lv_span_get_style(span), LV_OPA_50);
span = lv_spangroup_new_span(spans);
lv_span_set_text_static(span, "good good study, day day up.");
#if LV_FONT_MONTSERRAT_24
lv_style_set_text_font(lv_span_get_style(span), &lv_font_montserrat_24);
#endif
lv_style_set_text_color(lv_span_get_style(span), lv_palette_main(LV_PALETTE_GREEN));
span = lv_spangroup_new_span(spans);
lv_span_set_text_static(span, "LVGL is an open-source graphics library.");
lv_style_set_text_color(lv_span_get_style(span), lv_palette_main(LV_PALETTE_BLUE));
span = lv_spangroup_new_span(spans);
lv_span_set_text_static(span, "the boy no name.");
lv_style_set_text_color(lv_span_get_style(span), lv_palette_main(LV_PALETTE_GREEN));
#if LV_FONT_MONTSERRAT_20
lv_style_set_text_font(lv_span_get_style(span), &lv_font_montserrat_20);
#endif
lv_style_set_text_decor(lv_span_get_style(span), LV_TEXT_DECOR_UNDERLINE);
span = lv_spangroup_new_span(spans);
lv_span_set_text(span, "I have a dream that hope to come true.");
lv_style_set_text_decor(lv_span_get_style(span), LV_TEXT_DECOR_STRIKETHROUGH);
lv_spangroup_refr_mode(spans);
lv_obj_add_event_cb(spans, click_event_cb, LV_EVENT_CLICKED, NULL);
}
#endif
Spinbox（微调框）
Simple Spinbox
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_SPINBOX && LV_BUILD_EXAMPLES
static lv_obj_t * spinbox;
static void lv_spinbox_increment_event_cb(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
if(code == LV_EVENT_SHORT_CLICKED || code == LV_EVENT_LONG_PRESSED_REPEAT) {
lv_spinbox_increment(spinbox);
}
}
static void lv_spinbox_decrement_event_cb(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
if(code == LV_EVENT_SHORT_CLICKED || code == LV_EVENT_LONG_PRESSED_REPEAT) {
lv_spinbox_decrement(spinbox);
}
}
void lv_example_spinbox_1(void)
{
spinbox = lv_spinbox_create(lv_screen_active());
lv_spinbox_set_range(spinbox, -1000, 25000);
lv_spinbox_set_digit_format(spinbox, 5, 2);
lv_spinbox_step_prev(spinbox);
lv_obj_set_width(spinbox, 100);
lv_obj_center(spinbox);
int32_t h = lv_obj_get_height(spinbox);
lv_obj_t * btn = lv_button_create(lv_screen_active());
lv_obj_set_size(btn, h, h);
lv_obj_align_to(btn, spinbox, LV_ALIGN_OUT_RIGHT_MID, 5, 0);
lv_obj_set_style_bg_image_src(btn, LV_SYMBOL_PLUS, 0);
lv_obj_add_event_cb(btn, lv_spinbox_increment_event_cb, LV_EVENT_ALL, NULL);
btn = lv_button_create(lv_screen_active());
lv_obj_set_size(btn, h, h);
lv_obj_align_to(btn, spinbox, LV_ALIGN_OUT_LEFT_MID, -5, 0);
lv_obj_set_style_bg_image_src(btn, LV_SYMBOL_MINUS, 0);
lv_obj_add_event_cb(btn, lv_spinbox_decrement_event_cb, LV_EVENT_ALL, NULL);
}
#endif
Spinner（环形加载器）
Simple spinner
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_SPINNER && LV_BUILD_EXAMPLES
void lv_example_spinner_1(void)
{
/*Create a spinner*/
lv_obj_t * spinner = lv_spinner_create(lv_screen_active());
lv_obj_set_size(spinner, 100, 100);
lv_obj_center(spinner);
lv_spinner_set_anim_params(spinner, 10000, 200);
}
#endif
Switch（开关）
Simple Switch
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_SWITCH && LV_BUILD_EXAMPLES
static void event_handler(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * obj = lv_event_get_target(e);
if(code == LV_EVENT_VALUE_CHANGED) {
LV_UNUSED(obj);
LV_LOG_USER("State: %s\n", lv_obj_has_state(obj, LV_STATE_CHECKED) ? "On" : "Off");
}
}
void lv_example_switch_1(void)
{
lv_obj_set_flex_flow(lv_screen_active(), LV_FLEX_FLOW_COLUMN);
lv_obj_set_flex_align(lv_screen_active(), LV_FLEX_ALIGN_CENTER, LV_FLEX_ALIGN_CENTER, LV_FLEX_ALIGN_CENTER);
lv_obj_t * sw;
sw = lv_switch_create(lv_screen_active());
lv_obj_add_event_cb(sw, event_handler, LV_EVENT_ALL, NULL);
lv_obj_add_flag(sw, LV_OBJ_FLAG_EVENT_BUBBLE);
sw = lv_switch_create(lv_screen_active());
lv_obj_add_state(sw, LV_STATE_CHECKED);
lv_obj_add_event_cb(sw, event_handler, LV_EVENT_ALL, NULL);
sw = lv_switch_create(lv_screen_active());
lv_obj_add_state(sw, LV_STATE_DISABLED);
lv_obj_add_event_cb(sw, event_handler, LV_EVENT_ALL, NULL);
sw = lv_switch_create(lv_screen_active());
lv_obj_add_state(sw, LV_STATE_CHECKED | LV_STATE_DISABLED);
lv_obj_add_event_cb(sw, event_handler, LV_EVENT_ALL, NULL);
}
#endif
Switch Orientation
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_SWITCH && LV_BUILD_EXAMPLES
static void event_handler(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * obj = lv_event_get_target(e);
if(code == LV_EVENT_VALUE_CHANGED) {
LV_UNUSED(obj);
LV_LOG_USER("State: %s\n", lv_obj_has_state(obj, LV_STATE_CHECKED) ? "On" : "Off");
}
}
void lv_example_switch_2(void)
{
lv_obj_set_flex_flow(lv_screen_active(), LV_FLEX_FLOW_ROW);
lv_obj_set_flex_align(lv_screen_active(), LV_FLEX_ALIGN_CENTER, LV_FLEX_ALIGN_CENTER, LV_FLEX_ALIGN_CENTER);
lv_obj_t * sw;
sw = lv_switch_create(lv_screen_active());
lv_obj_set_size(sw, 30, 60);
lv_obj_add_event_cb(sw, event_handler, LV_EVENT_ALL, NULL);
sw = lv_switch_create(lv_screen_active());
lv_obj_set_size(sw, 30, 60);
lv_switch_set_orientation(sw, LV_SWITCH_ORIENTATION_VERTICAL);
lv_obj_add_state(sw, LV_STATE_CHECKED);
lv_obj_add_event_cb(sw, event_handler, LV_EVENT_ALL, NULL);
}
#endif
Table（表格）
Simple table
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_TABLE && LV_BUILD_EXAMPLES
static void draw_event_cb(lv_event_t * e)
{
lv_draw_task_t * draw_task = lv_event_get_draw_task(e);
lv_draw_dsc_base_t * base_dsc = lv_draw_task_get_draw_dsc(draw_task);
/*If the cells are drawn...*/
if(base_dsc->part == LV_PART_ITEMS) {
uint32_t row = base_dsc->id1;
uint32_t col = base_dsc->id2;
/*Make the texts in the first cell center aligned*/
if(row == 0) {
lv_draw_label_dsc_t * label_draw_dsc = lv_draw_task_get_label_dsc(draw_task);
if(label_draw_dsc) {
label_draw_dsc->align = LV_TEXT_ALIGN_CENTER;
}
lv_draw_fill_dsc_t * fill_draw_dsc = lv_draw_task_get_fill_dsc(draw_task);
if(fill_draw_dsc) {
fill_draw_dsc->color = lv_color_mix(lv_palette_main(LV_PALETTE_BLUE), fill_draw_dsc->color, LV_OPA_20);
fill_draw_dsc->opa = LV_OPA_COVER;
}
}
/*In the first column align the texts to the right*/
else if(col == 0) {
lv_draw_label_dsc_t * label_draw_dsc = lv_draw_task_get_label_dsc(draw_task);
if(label_draw_dsc) {
label_draw_dsc->align = LV_TEXT_ALIGN_RIGHT;
}
}
/*Make every 2nd row grayish*/
if((row != 0 && row % 2) == 0) {
lv_draw_fill_dsc_t * fill_draw_dsc = lv_draw_task_get_fill_dsc(draw_task);
if(fill_draw_dsc) {
fill_draw_dsc->color = lv_color_mix(lv_palette_main(LV_PALETTE_GREY), fill_draw_dsc->color, LV_OPA_10);
fill_draw_dsc->opa = LV_OPA_COVER;
}
}
}
}
void lv_example_table_1(void)
{
lv_obj_t * table = lv_table_create(lv_screen_active());
/*Fill the first column*/
lv_table_set_cell_value(table, 0, 0, "Name");
lv_table_set_cell_value(table, 1, 0, "Apple");
lv_table_set_cell_value(table, 2, 0, "Banana");
lv_table_set_cell_value(table, 3, 0, "Lemon");
lv_table_set_cell_value(table, 4, 0, "Grape");
lv_table_set_cell_value(table, 5, 0, "Melon");
lv_table_set_cell_value(table, 6, 0, "Peach");
lv_table_set_cell_value(table, 7, 0, "Nuts");
/*Fill the second column*/
lv_table_set_cell_value(table, 0, 1, "Price");
lv_table_set_cell_value(table, 1, 1, "$7");
lv_table_set_cell_value(table, 2, 1, "$4");
lv_table_set_cell_value(table, 3, 1, "$6");
lv_table_set_cell_value(table, 4, 1, "$2");
lv_table_set_cell_value(table, 5, 1, "$5");
lv_table_set_cell_value(table, 6, 1, "$1");
lv_table_set_cell_value(table, 7, 1, "$9");
/*Set a smaller height to the table. It'll make it scrollable*/
lv_obj_set_height(table, 200);
lv_obj_center(table);
/*Add an event callback to to apply some custom drawing*/
lv_obj_add_event_cb(table, draw_event_cb, LV_EVENT_DRAW_TASK_ADDED, NULL);
lv_obj_add_flag(table, LV_OBJ_FLAG_SEND_DRAW_TASK_EVENTS);
}
#endif
Lightweighted list from table
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_TABLE && LV_BUILD_EXAMPLES
#define ITEM_CNT 200
static void draw_event_cb(lv_event_t * e)
{
lv_obj_t * obj = lv_event_get_target(e);
lv_draw_task_t * draw_task = lv_event_get_draw_task(e);
lv_draw_dsc_base_t * base_dsc = lv_draw_task_get_draw_dsc(draw_task);
/*If the cells are drawn...*/
if(base_dsc->part == LV_PART_ITEMS && lv_draw_task_get_type(draw_task) == LV_DRAW_TASK_TYPE_FILL) {
/*Draw the background*/
bool chk = lv_table_has_cell_ctrl(obj, base_dsc->id1, 0, LV_TABLE_CELL_CTRL_CUSTOM_1);
lv_draw_rect_dsc_t rect_dsc;
lv_draw_rect_dsc_init(&rect_dsc);
rect_dsc.bg_color = chk ? lv_theme_get_color_primary(obj) : lv_palette_lighten(LV_PALETTE_GREY, 2);
rect_dsc.radius = LV_RADIUS_CIRCLE;
lv_area_t sw_area;
sw_area.x1 = 0;
sw_area.x2 = 40;
sw_area.y1 = 0;
sw_area.y2 = 24;
lv_area_t draw_task_area;
lv_draw_task_get_area(draw_task, &draw_task_area);
lv_area_align(&draw_task_area, &sw_area, LV_ALIGN_RIGHT_MID, -15, 0);
lv_draw_rect(base_dsc->layer, &rect_dsc, &sw_area);
/*Draw the knob*/
rect_dsc.bg_color = lv_color_white();
lv_area_t knob_area;
knob_area.x1 = 0;
knob_area.x2 = 18;
knob_area.y1 = 0;
knob_area.y2 = 18;
if(chk) {
lv_area_align(&sw_area, &knob_area, LV_ALIGN_RIGHT_MID, -3, 0);
}
else {
lv_area_align(&sw_area, &knob_area, LV_ALIGN_LEFT_MID, 3, 0);
}
lv_draw_rect(base_dsc->layer, &rect_dsc, &knob_area);
}
}
static void change_event_cb(lv_event_t * e)
{
lv_obj_t * obj = lv_event_get_target(e);
uint32_t col;
uint32_t row;
lv_table_get_selected_cell(obj, &row, &col);
bool chk = lv_table_has_cell_ctrl(obj, row, 0, LV_TABLE_CELL_CTRL_CUSTOM_1);
if(chk) lv_table_clear_cell_ctrl(obj, row, 0, LV_TABLE_CELL_CTRL_CUSTOM_1);
else lv_table_add_cell_ctrl(obj, row, 0, LV_TABLE_CELL_CTRL_CUSTOM_1);
}
/**
* A very light-weighted list created from table
*/
void lv_example_table_2(void)
{
/*Measure memory usage*/
lv_mem_monitor_t mon1;
lv_mem_monitor(&mon1);
uint32_t t = lv_tick_get();
lv_obj_t * table = lv_table_create(lv_screen_active());
/*Set a smaller height to the table. It'll make it scrollable*/
lv_obj_set_size(table, LV_SIZE_CONTENT, 200);
lv_table_set_column_width(table, 0, 150);
lv_table_set_row_count(table, ITEM_CNT); /*Not required but avoids a lot of memory reallocation lv_table_set_set_value*/
lv_table_set_column_count(table, 1);
/*Don't make the cell pressed, we will draw something different in the event*/
lv_obj_remove_style(table, NULL, LV_PART_ITEMS | LV_STATE_PRESSED);
uint32_t i;
for(i = 0; i < ITEM_CNT; i++) {
lv_table_set_cell_value_fmt(table, i, 0, "Item %"LV_PRIu32, i + 1);
}
lv_obj_align(table, LV_ALIGN_CENTER, 0, -20);
/*Add an event callback to to apply some custom drawing*/
lv_obj_add_event_cb(table, draw_event_cb, LV_EVENT_DRAW_TASK_ADDED, NULL);
lv_obj_add_event_cb(table, change_event_cb, LV_EVENT_VALUE_CHANGED, NULL);
lv_obj_add_flag(table, LV_OBJ_FLAG_SEND_DRAW_TASK_EVENTS);
lv_mem_monitor_t mon2;
lv_mem_monitor(&mon2);
size_t mem_used = mon1.free_size - mon2.free_size;
uint32_t elaps = lv_tick_elaps(t);
lv_obj_t * label = lv_label_create(lv_screen_active());
lv_label_set_text_fmt(label, "%"LV_PRIu32" items were created in %"LV_PRIu32" ms\n"
"using %zu bytes of memory",
(uint32_t)ITEM_CNT, elaps, mem_used);
lv_obj_align(label, LV_ALIGN_BOTTOM_MID, 0, -10);
}
#endif
Tabview（选项卡）
Simple Tabview
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_TABVIEW && LV_BUILD_EXAMPLES
void lv_example_tabview_1(void)
{
/*Create a Tab view object*/
lv_obj_t * tabview;
tabview = lv_tabview_create(lv_screen_active());
/*Add 3 tabs (the tabs are page (lv_page) and can be scrolled*/
lv_obj_t * tab1 = lv_tabview_add_tab(tabview, "Tab 1");
lv_obj_t * tab2 = lv_tabview_add_tab(tabview, "Tab 2");
lv_obj_t * tab3 = lv_tabview_add_tab(tabview, "Tab 3");
/*Add content to the tabs*/
lv_obj_t * label = lv_label_create(tab1);
lv_label_set_text(label, "This the first tab\n\n"
"If the content\n"
"of a tab\n"
"becomes too\n"
"longer\n"
"than the\n"
"container\n"
"then it\n"
"automatically\n"
"becomes\n"
"scrollable.\n"
"\n"
"\n"
"\n"
"Can you see it?");
label = lv_label_create(tab2);
lv_label_set_text(label, "Second tab");
label = lv_label_create(tab3);
lv_label_set_text(label, "Third tab");
lv_obj_scroll_to_view_recursive(label, LV_ANIM_ON);
}
#endif
Tabs on the left, styling and no scrolling
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_TABVIEW && LV_BUILD_EXAMPLES
/*A vertical tab view with disabled scrolling and some styling*/
void lv_example_tabview_2(void)
{
/*Create a Tab view object*/
lv_obj_t * tabview;
tabview = lv_tabview_create(lv_screen_active());
lv_tabview_set_tab_bar_position(tabview, LV_DIR_LEFT);
lv_tabview_set_tab_bar_size(tabview, 80);
lv_obj_set_style_bg_color(tabview, lv_palette_lighten(LV_PALETTE_RED, 2), 0);
lv_obj_t * tab_buttons = lv_tabview_get_tab_bar(tabview);
lv_obj_set_style_bg_color(tab_buttons, lv_palette_darken(LV_PALETTE_GREY, 3), 0);
lv_obj_set_style_text_color(tab_buttons, lv_palette_lighten(LV_PALETTE_GREY, 5), 0);
lv_obj_set_style_border_side(tab_buttons, LV_BORDER_SIDE_RIGHT, LV_PART_ITEMS | LV_STATE_CHECKED);
/*Add 3 tabs (the tabs are page (lv_page) and can be scrolled*/
lv_obj_t * tab1 = lv_tabview_add_tab(tabview, "Tab 1");
lv_obj_t * tab2 = lv_tabview_add_tab(tabview, "Tab 2");
lv_obj_t * tab3 = lv_tabview_add_tab(tabview, "Tab 3");
lv_obj_t * tab4 = lv_tabview_add_tab(tabview, "Tab 4");
lv_obj_t * tab5 = lv_tabview_add_tab(tabview, "Tab 5");
lv_obj_set_style_bg_color(tab2, lv_palette_lighten(LV_PALETTE_AMBER, 3), 0);
lv_obj_set_style_bg_opa(tab2, LV_OPA_COVER, 0);
/*Add content to the tabs*/
lv_obj_t * label = lv_label_create(tab1);
lv_label_set_text(label, "First tab");
label = lv_label_create(tab2);
lv_label_set_text(label, "Second tab");
label = lv_label_create(tab3);
lv_label_set_text(label, "Third tab");
label = lv_label_create(tab4);
lv_label_set_text(label, "Forth tab");
label = lv_label_create(tab5);
lv_label_set_text(label, "Fifth tab");
lv_obj_remove_flag(lv_tabview_get_content(tabview), LV_OBJ_FLAG_SCROLLABLE);
}
#endif
Textarea（文本框）
Simple Text area
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_TEXTAREA && LV_BUILD_EXAMPLES
static void textarea_event_handler(lv_event_t * e)
{
lv_obj_t * ta = lv_event_get_target(e);
LV_UNUSED(ta);
LV_LOG_USER("Enter was pressed. The current text is: %s", lv_textarea_get_text(ta));
}
static void btnm_event_handler(lv_event_t * e)
{
lv_obj_t * obj = lv_event_get_target(e);
lv_obj_t * ta = lv_event_get_user_data(e);
const char * txt = lv_buttonmatrix_get_button_text(obj, lv_buttonmatrix_get_selected_button(obj));
if(lv_strcmp(txt, LV_SYMBOL_BACKSPACE) == 0) lv_textarea_delete_char(ta);
else if(lv_strcmp(txt, LV_SYMBOL_NEW_LINE) == 0) lv_obj_send_event(ta, LV_EVENT_READY, NULL);
else lv_textarea_add_text(ta, txt);
}
void lv_example_textarea_1(void)
{
lv_obj_t * ta = lv_textarea_create(lv_screen_active());
lv_textarea_set_one_line(ta, true);
lv_obj_align(ta, LV_ALIGN_TOP_MID, 0, 10);
lv_obj_add_event_cb(ta, textarea_event_handler, LV_EVENT_READY, ta);
lv_obj_add_state(ta, LV_STATE_FOCUSED); /*To be sure the cursor is visible*/
static const char * btnm_map[] = {"1", "2", "3", "\n",
"4", "5", "6", "\n",
"7", "8", "9", "\n",
LV_SYMBOL_BACKSPACE, "0", LV_SYMBOL_NEW_LINE, ""
};
lv_obj_t * btnm = lv_buttonmatrix_create(lv_screen_active());
lv_obj_set_size(btnm, 200, 150);
lv_obj_align(btnm, LV_ALIGN_BOTTOM_MID, 0, -10);
lv_obj_add_event_cb(btnm, btnm_event_handler, LV_EVENT_VALUE_CHANGED, ta);
lv_obj_remove_flag(btnm, LV_OBJ_FLAG_CLICK_FOCUSABLE); /*To keep the text area focused on button clicks*/
lv_buttonmatrix_set_map(btnm, btnm_map);
}
#endif
Text area with password field
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_TEXTAREA && LV_USE_KEYBOARD && LV_BUILD_EXAMPLES
static void ta_event_cb(lv_event_t * e);
static lv_obj_t * kb;
void lv_example_textarea_2(void)
{
/*Create the password box*/
lv_obj_t * pwd_ta = lv_textarea_create(lv_screen_active());
lv_textarea_set_text(pwd_ta, "");
lv_textarea_set_password_mode(pwd_ta, true);
lv_textarea_set_one_line(pwd_ta, true);
lv_obj_set_width(pwd_ta, lv_pct(40));
lv_obj_set_pos(pwd_ta, 5, 20);
lv_obj_add_event_cb(pwd_ta, ta_event_cb, LV_EVENT_ALL, NULL);
/*Create a label and position it above the text box*/
lv_obj_t * pwd_label = lv_label_create(lv_screen_active());
lv_label_set_text(pwd_label, "Password:");
lv_obj_align_to(pwd_label, pwd_ta, LV_ALIGN_OUT_TOP_LEFT, 0, 0);
/*Create the one-line mode text area*/
lv_obj_t * text_ta = lv_textarea_create(lv_screen_active());
lv_textarea_set_one_line(text_ta, true);
lv_textarea_set_password_mode(text_ta, false);
lv_obj_set_width(text_ta, lv_pct(40));
lv_obj_add_event_cb(text_ta, ta_event_cb, LV_EVENT_ALL, NULL);
lv_obj_align(text_ta, LV_ALIGN_TOP_RIGHT, -5, 20);
/*Create a label and position it above the text box*/
lv_obj_t * oneline_label = lv_label_create(lv_screen_active());
lv_label_set_text(oneline_label, "Text:");
lv_obj_align_to(oneline_label, text_ta, LV_ALIGN_OUT_TOP_LEFT, 0, 0);
/*Create a keyboard*/
kb = lv_keyboard_create(lv_screen_active());
lv_obj_set_size(kb, LV_HOR_RES, LV_VER_RES / 2);
lv_keyboard_set_textarea(kb, pwd_ta); /*Focus it on one of the text areas to start*/
/*The keyboard will show Arabic characters if they are enabled */
#if LV_USE_ARABIC_PERSIAN_CHARS && LV_FONT_DEJAVU_16_PERSIAN_HEBREW
lv_obj_set_style_text_font(kb, &lv_font_dejavu_16_persian_hebrew, 0);
lv_obj_set_style_text_font(text_ta, &lv_font_dejavu_16_persian_hebrew, 0);
lv_obj_set_style_text_font(pwd_ta, &lv_font_dejavu_16_persian_hebrew, 0);
#endif
}
static void ta_event_cb(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * ta = lv_event_get_target(e);
if(code == LV_EVENT_CLICKED || code == LV_EVENT_FOCUSED) {
/*Focus on the clicked text area*/
if(kb != NULL) lv_keyboard_set_textarea(kb, ta);
}
else if(code == LV_EVENT_READY) {
LV_LOG_USER("Ready, current text: %s", lv_textarea_get_text(ta));
}
}
#endif
Text auto-formatting
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_TEXTAREA && LV_USE_KEYBOARD && LV_BUILD_EXAMPLES
static void ta_event_cb(lv_event_t * e);
static lv_obj_t * kb;
/**
* Automatically format text like a clock. E.g. "12:34"
* Add the ':' automatically.
*/
void lv_example_textarea_3(void)
{
/*Create the text area*/
lv_obj_t * ta = lv_textarea_create(lv_screen_active());
lv_obj_add_event_cb(ta, ta_event_cb, LV_EVENT_VALUE_CHANGED, NULL);
lv_textarea_set_accepted_chars(ta, "0123456789:");
lv_textarea_set_max_length(ta, 5);
lv_textarea_set_one_line(ta, true);
lv_textarea_set_text(ta, "");
/*Create a keyboard*/
kb = lv_keyboard_create(lv_screen_active());
lv_obj_set_size(kb, LV_HOR_RES, LV_VER_RES / 2);
lv_keyboard_set_mode(kb, LV_KEYBOARD_MODE_NUMBER);
lv_keyboard_set_textarea(kb, ta);
}
static void ta_event_cb(lv_event_t * e)
{
lv_obj_t * ta = lv_event_get_target(e);
const char * txt = lv_textarea_get_text(ta);
if(txt[0] >= '0' && txt[0] <= '9' &&
txt[1] >= '0' && txt[1] <= '9' &&
txt[2] != ':') {
lv_textarea_set_cursor_pos(ta, 2);
lv_textarea_add_char(ta, ':');
}
}
#endif
Tileview（平铺视图）
Tileview with content
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_TILEVIEW && LV_BUILD_EXAMPLES
/**
* Create a 2x2 tile view and allow scrolling only in an "L" shape.
* Demonstrate scroll chaining with a long list that
* scrolls the tile view when it can't be scrolled further.
*/
void lv_example_tileview_1(void)
{
lv_obj_t * tv = lv_tileview_create(lv_screen_active());
/*Tile1: just a label*/
lv_obj_t * tile1 = lv_tileview_add_tile(tv, 0, 0, LV_DIR_BOTTOM);
lv_obj_t * label = lv_label_create(tile1);
lv_label_set_text(label, "Scroll down");
lv_obj_center(label);
/*Tile2: a button*/
lv_obj_t * tile2 = lv_tileview_add_tile(tv, 0, 1, LV_DIR_TOP | LV_DIR_RIGHT);
lv_obj_t * btn = lv_button_create(tile2);
label = lv_label_create(btn);
lv_label_set_text(label, "Scroll up or right");
lv_obj_set_size(btn, LV_SIZE_CONTENT, LV_SIZE_CONTENT);
lv_obj_center(btn);
/*Tile3: a list*/
lv_obj_t * tile3 = lv_tileview_add_tile(tv, 1, 1, LV_DIR_LEFT);
lv_obj_t * list = lv_list_create(tile3);
lv_obj_set_size(list, LV_PCT(100), LV_PCT(100));
lv_list_add_button(list, NULL, "One");
lv_list_add_button(list, NULL, "Two");
lv_list_add_button(list, NULL, "Three");
lv_list_add_button(list, NULL, "Four");
lv_list_add_button(list, NULL, "Five");
lv_list_add_button(list, NULL, "Six");
lv_list_add_button(list, NULL, "Seven");
lv_list_add_button(list, NULL, "Eight");
lv_list_add_button(list, NULL, "Nine");
lv_list_add_button(list, NULL, "Ten");
}
#endif
Window（窗口）
Simple window
C code
View on GitHub#include "../../lv_examples.h"
#if LV_USE_WIN && LV_BUILD_EXAMPLES
static void event_handler(lv_event_t * e)
{
lv_obj_t * obj = lv_event_get_target(e);
LV_UNUSED(obj);
LV_LOG_USER("Button %d clicked", (int)lv_obj_get_index(obj));
}
void lv_example_win_1(void)
{
lv_obj_t * win = lv_win_create(lv_screen_active());
lv_obj_t * btn;
btn = lv_win_add_button(win, LV_SYMBOL_LEFT, 40);
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
lv_win_add_title(win, "A title");
btn = lv_win_add_button(win, LV_SYMBOL_RIGHT, 40);
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_win_add_button(win, LV_SYMBOL_CLOSE, 60);
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
lv_obj_t * cont = lv_win_get_content(win); /*Content can be added here*/
lv_obj_t * label = lv_label_create(cont);
lv_label_set_text(label, "This is\n"
"a pretty\n"
"long text\n"
"to see how\n"
"the window\n"
"becomes\n"
"scrollable.\n"
"\n"
"\n"
"Some more\n"
"text to be\n"
"sure it\n"
"overflows. :)");
}
#endif