LED (lv_led)¶

概述¶

LED 是一个类似矩形（或圆形）的对象，其亮度可以调整。亮度较低时，LED 的颜色会变暗。

部件和样式¶

LED 只有一个主要部件，称为 LV_LED_PART_MAIN，它使用所有典型的背景样式属性。

用法¶

颜色¶

可以使用 lv_led_set_color(led, lv_color_hex(0xff0080)) 设置 LED 的颜色。此颜色将用作背景颜色、边框颜色和阴影颜色。

亮度¶

可以使用 lv_led_set_bright(led, bright) 设置亮度。亮度应在 0（最暗）到 255（最亮）之间。

切换¶

使用 lv_led_on(led) 和 lv_led_off(led) 将亮度设置为预定义的打开或关闭值。lv_led_toggle(led) 在打开和关闭状态之间切换。

事件¶

LV_EVENT_DRAW_PART_BEGIN 和 LV_EVENT_DRAW_PART_END 会针对以下类型发送：
- LV_LED_DRAW_PART_RECTANGLE 主矩形。LV_OBJ_DRAW_PART_RECTANGLE 不会由基础对象发送。
  - part: LV_PART_MAIN
  - rect_dsc
  - draw_area: 矩形的区域

也可以查看基础对象的事件。

了解更多关于事件的信息。

按键¶

此对象类型不处理任何按键。

了解更多关于按键的信息。

示例¶

LED with custom style¶

#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_scr_act());
    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_scr_act());
    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_scr_act());
    lv_obj_align(led3, LV_ALIGN_CENTER, 80, 0);
    lv_led_on(led3);
}

#endif

#
# Create LED's with different brightness and color
#

# Create a LED and switch it OFF
led1  = lv.led(lv.scr_act())
led1.align(lv.ALIGN.CENTER, -80, 0)
led1.off()

# Copy the previous LED and set a brightness
led2  = lv.led(lv.scr_act())
led2.align(lv.ALIGN.CENTER, 0, 0)
led2.set_brightness(150)
led2.set_color(lv.palette_main(lv.PALETTE.RED))

# Copy the previous LED and switch it ON
led3  = lv.led(lv.scr_act())
led3.align(lv.ALIGN.CENTER, 80, 0)
led3.on()

API¶

Enums

enum lv_led_draw_part_type_t¶

type field in lv_obj_draw_part_dsc_t if class_p = lv_led_class Used in LV_EVENT_DRAW_PART_BEGIN and LV_EVENT_DRAW_PART_END

Values:

enumerator LV_LED_DRAW_PART_RECTANGLE¶: The main rectangle

Functions

lv_obj_t *lv_led_create(lv_obj_t *parent)¶

Create a led object

Parameters: parent -- pointer to an object, it will be the parent of the new led
Returns: pointer to the created led

void lv_led_set_color(lv_obj_t *led, lv_color_t color)¶

Set the color of the LED

Parameters

led -- pointer to a LED object
color -- the color of the LED

void lv_led_set_brightness(lv_obj_t *led, uint8_t bright)¶

Set the brightness of a LED object

Parameters

led -- pointer to a LED object
bright -- LV_LED_BRIGHT_MIN (max. dark) ... LV_LED_BRIGHT_MAX (max. light)

void lv_led_on(lv_obj_t *led)¶

Light on a LED

Parameters: led -- pointer to a LED object

void lv_led_off(lv_obj_t *led)¶

Light off a LED

Parameters: led -- pointer to a LED object

void lv_led_toggle(lv_obj_t *led)¶

Toggle the state of a LED

Parameters: led -- pointer to a LED object

uint8_t lv_led_get_brightness(const lv_obj_t *obj)¶

Get the brightness of a LEd object

Parameters: led -- pointer to LED object
Returns: bright 0 (max. dark) ... 255 (max. light)

Variables

const lv_obj_class_t lv_led_class¶

struct lv_led_t¶

Public Members

lv_obj_t obj¶

lv_color_t color¶

uint8_t bright¶: Current brightness of the LED (0..255)