仪表 (lv_meter)¶

概述¶

仪表小部件可以以非常灵活的方式可视化数据。它可以显示弧线、指针、刻度线和标签。

部件和样式¶

LV_PART_MAIN 仪表的背景。使用典型的背景属性。
LV_PART_TICK 刻度线和标签，使用 line 和 text 样式属性。
LV_PART_INDICATOR 指针线或图像，使用 line 和 img 样式属性，以及背景属性在指针的枢轴上绘制一个方形（或圆形）。填充使方形更大。
LV_PART_ITEMS 弧线，使用 arc 属性。

用法¶

添加刻度¶

首先需要使用 lv_meter_scale_t * scale = lv_meter_add_scale(meter) 向仪表添加一个刻度。刻度有次要和主要刻度线，以及主要刻度线上的标签。稍后可以向仪表添加指针（指针、弧线、刻度修改器）。

可以向仪表添加任意数量的刻度。

次要刻度线可以通过以下方式配置：lv_meter_set_scale_ticks(meter, scale, tick_count, line_width, tick_length, tick_color)。

要添加主要刻度线，请使用 lv_meter_set_scale_major_ticks(meter, scale, nth_major, tick_width, tick_length, tick_color, label_gap)。nth_major 指定跳过多少个次要刻度以绘制一个主要刻度。

标签会自动添加到主要刻度上，距离刻度 label_gap，文本与刻度线的值成比例。

lv_meter_set_scale_range(meter, scale, min, max, angle_range, rotation) 设置刻度的值和角度范围。

添加指针¶

指针需要添加到刻度上，其值在刻度范围内解释。

所有添加指针的函数返回 lv_meter_indicator_t *。

指针线¶

indic = lv_meter_add_needle_line(meter, scale, line_width, line_color, r_mod) 向刻度添加指针线。默认情况下，线的长度与刻度的半径相同，但 r_mod 会更改长度。

lv_meter_set_indicator_value(meter, indic, value) 设置指针的值。

指针图像¶

indic = lv_meter_add_needle_img(meter, scale, img_src, pivot_x, pivot_y) 设置一个图像作为指针。img_src 应该是一个指向右侧的指针，例如 -O--->。 pivot_x 和 pivot_y 设置相对于图像左上角的旋转枢轴点。

lv_meter_set_indicator_value(meter, indicator, value) 设置指针的值。

弧线¶

indic = lv_meter_add_arc(meter, scale, arc_width, arc_color, r_mod) 添加弧线指针。默认情况下，弧线的半径与刻度的半径相同，但 r_mod 会更改半径。

lv_meter_set_indicator_start_value(meter, indic, value) 和 lv_meter_set_indicator_end_value(meter, indicator, value) 设置指针的值。

刻度线（ticks）¶

indic = lv_meter_add_scale_lines(meter, scale, color_start, color_end, local, width_mod) 添加一个修改刻度线的指针。如果 local 为 true，刻度线的颜色将在指针的起始值和结束值范围内从 color_start 渐变到 color_end。如果 local 为 false，color_start 和 color_end 将映射到刻度的起始值和结束值，并且只有该颜色渐变的“切片”将在指针的起始值和结束值范围内可见。 width_mod 修改刻度线的宽度。

lv_meter_set_indicator_start_value(meter, indicator, value) 和 lv_meter_set_indicator_end_value(meter, indicator, value) 设置指针的值。

事件¶

LV_EVENT_DRAW_PART_BEGIN 和 LV_EVENT_DRAW_PART_END 会针对以下类型发送：
- LV_METER_DRAW_PART_ARC 弧线指针
  - part: LV_PART_ITEMS
  - sub_part_ptr: 指向指针的指针
  - arc_dsc
  - radius: 弧线的半径
  - p1 弧线的中心
- LV_METER_DRAW_PART_NEEDLE_LINE 指针线
  - part: LV_PART_ITEMS
  - p1, p2 线的点
  - line_dsc
  - sub_part_ptr: 指向指针的指针
- LV_METER_DRAW_PART_NEEDLE_IMG 指针图像
  - part: LV_PART_ITEMS
  - p1, p2 线的点
  - img_dsc
  - sub_part_ptr: 指向指针的指针
- LV_METER_DRAW_PART_TICK 刻度线和标签
  - part: LV_PART_TICKS
  - value: 线的值
  - text: value 转换为十进制或次要线上的 NULL
  - label_dsc: 标签绘制描述符或次要线上的 NULL
  - line_dsc
  - id: 线的索引

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¶

仪表小部件不处理任何按键。

了解更多关于按键的信息。

示例¶

Simple meter¶

#include "../../lv_examples.h"
#if LV_USE_METER && LV_BUILD_EXAMPLES

static lv_obj_t * meter;

static void set_value(void * indic, int32_t v)
{
    lv_meter_set_indicator_value(meter, indic, v);
}

/**
 * A simple meter
 */
void lv_example_meter_1(void)
{
    meter = lv_meter_create(lv_scr_act());
    lv_obj_center(meter);
    lv_obj_set_size(meter, 200, 200);

    /*Add a scale first*/
    lv_meter_scale_t * scale = lv_meter_add_scale(meter);
    lv_meter_set_scale_ticks(meter, scale, 41, 2, 10, lv_palette_main(LV_PALETTE_GREY));
    lv_meter_set_scale_major_ticks(meter, scale, 8, 4, 15, lv_color_black(), 10);

    lv_meter_indicator_t * indic;

    /*Add a blue arc to the start*/
    indic = lv_meter_add_arc(meter, scale, 3, lv_palette_main(LV_PALETTE_BLUE), 0);
    lv_meter_set_indicator_start_value(meter, indic, 0);
    lv_meter_set_indicator_end_value(meter, indic, 20);

    /*Make the tick lines blue at the start of the scale*/
    indic = lv_meter_add_scale_lines(meter, scale, lv_palette_main(LV_PALETTE_BLUE), lv_palette_main(LV_PALETTE_BLUE),
                                     false, 0);
    lv_meter_set_indicator_start_value(meter, indic, 0);
    lv_meter_set_indicator_end_value(meter, indic, 20);

    /*Add a red arc to the end*/
    indic = lv_meter_add_arc(meter, scale, 3, lv_palette_main(LV_PALETTE_RED), 0);
    lv_meter_set_indicator_start_value(meter, indic, 80);
    lv_meter_set_indicator_end_value(meter, indic, 100);

    /*Make the tick lines red at the end of the scale*/
    indic = lv_meter_add_scale_lines(meter, scale, lv_palette_main(LV_PALETTE_RED), lv_palette_main(LV_PALETTE_RED), false,
                                     0);
    lv_meter_set_indicator_start_value(meter, indic, 80);
    lv_meter_set_indicator_end_value(meter, indic, 100);

    /*Add a needle line indicator*/
    indic = lv_meter_add_needle_line(meter, scale, 4, lv_palette_main(LV_PALETTE_GREY), -10);

    /*Create an animation to set the value*/
    lv_anim_t a;
    lv_anim_init(&a);
    lv_anim_set_exec_cb(&a, set_value);
    lv_anim_set_var(&a, indic);
    lv_anim_set_values(&a, 0, 100);
    lv_anim_set_time(&a, 2000);
    lv_anim_set_repeat_delay(&a, 100);
    lv_anim_set_playback_time(&a, 500);
    lv_anim_set_playback_delay(&a, 100);
    lv_anim_set_repeat_count(&a, LV_ANIM_REPEAT_INFINITE);
    lv_anim_start(&a);
}

#endif

#!//opt/bin/lv_micropython -i
import utime as time
import lvgl as lv
import display_driver

def set_value(indic, v):
    meter.set_indicator_value(indic, v)

#
# A simple meter
#
meter = lv.meter(lv.scr_act())
meter.center()
meter.set_size(200, 200)

# Add a scale first
scale = meter.add_scale()
meter.set_scale_ticks(scale, 51, 2, 10, lv.palette_main(lv.PALETTE.GREY))
meter.set_scale_major_ticks(scale, 10, 4, 15, lv.color_black(), 10)

indic = lv.meter_indicator_t()

# Add a blue arc to the start
indic = meter.add_arc(scale, 3, lv.palette_main(lv.PALETTE.BLUE), 0)
meter.set_indicator_start_value(indic, 0)
meter.set_indicator_end_value(indic, 20)

# Make the tick lines blue at the start of the scale
indic = meter.add_scale_lines(scale, lv.palette_main(lv.PALETTE.BLUE), lv.palette_main(lv.PALETTE.BLUE), False, 0)
meter.set_indicator_start_value(indic, 0)
meter.set_indicator_end_value(indic, 20)

# Add a red arc to the end
indic = meter.add_arc(scale, 3, lv.palette_main(lv.PALETTE.RED), 0)
meter.set_indicator_start_value(indic, 80)
meter.set_indicator_end_value(indic, 100)

# Make the tick lines red at the end of the scale
indic = meter.add_scale_lines(scale, lv.palette_main(lv.PALETTE.RED), lv.palette_main(lv.PALETTE.RED), False, 0)
meter.set_indicator_start_value(indic, 80)
meter.set_indicator_end_value(indic, 100)

# Add a needle line indicator
indic = meter.add_needle_line(scale, 4, lv.palette_main(lv.PALETTE.GREY), -10)

# Create an animation to set the value
a = lv.anim_t()
a.init()
a.set_var(indic)
a.set_values(0, 100)
a.set_time(2000)
a.set_repeat_delay(100)
a.set_playback_time(500)
a.set_playback_delay(100)
a.set_repeat_count(lv.ANIM_REPEAT.INFINITE)
a.set_custom_exec_cb(lambda a,val: set_value(indic,val))
lv.anim_t.start(a)

A meter with multiple arcs¶

#include "../../lv_examples.h"
#if LV_USE_METER && LV_BUILD_EXAMPLES

static lv_obj_t * meter;

static void set_value(void * indic, int32_t v)
{
    lv_meter_set_indicator_end_value(meter, indic, v);
}


/**
 * A meter with multiple arcs
 */
void lv_example_meter_2(void)
{
    meter = lv_meter_create(lv_scr_act());
    lv_obj_center(meter);
    lv_obj_set_size(meter, 200, 200);

    /*Remove the circle from the middle*/
    lv_obj_remove_style(meter, NULL, LV_PART_INDICATOR);

    /*Add a scale first*/
    lv_meter_scale_t * scale = lv_meter_add_scale(meter);
    lv_meter_set_scale_ticks(meter, scale, 11, 2, 10, lv_palette_main(LV_PALETTE_GREY));
    lv_meter_set_scale_major_ticks(meter, scale, 1, 2, 30, lv_color_hex3(0xeee), 15);
    lv_meter_set_scale_range(meter, scale, 0, 100, 270, 90);

    /*Add a three arc indicator*/
    lv_meter_indicator_t * indic1 = lv_meter_add_arc(meter, scale, 10, lv_palette_main(LV_PALETTE_RED), 0);
    lv_meter_indicator_t * indic2 = lv_meter_add_arc(meter, scale, 10, lv_palette_main(LV_PALETTE_GREEN), -10);
    lv_meter_indicator_t * indic3 = lv_meter_add_arc(meter, scale, 10, lv_palette_main(LV_PALETTE_BLUE), -20);

    /*Create an animation to set the value*/
    lv_anim_t a;
    lv_anim_init(&a);
    lv_anim_set_exec_cb(&a, set_value);
    lv_anim_set_values(&a, 0, 100);
    lv_anim_set_repeat_delay(&a, 100);
    lv_anim_set_playback_delay(&a, 100);
    lv_anim_set_repeat_count(&a, LV_ANIM_REPEAT_INFINITE);

    lv_anim_set_time(&a, 2000);
    lv_anim_set_playback_time(&a, 500);
    lv_anim_set_var(&a, indic1);
    lv_anim_start(&a);

    lv_anim_set_time(&a, 1000);
    lv_anim_set_playback_time(&a, 1000);
    lv_anim_set_var(&a, indic2);
    lv_anim_start(&a);

    lv_anim_set_time(&a, 1000);
    lv_anim_set_playback_time(&a, 2000);
    lv_anim_set_var(&a, indic3);
    lv_anim_start(&a);
}

#endif

#!//opt/bin/lv_micropython -i
import utime as time
import lvgl as lv
import display_driver

def set_value(indic,v):
    meter.set_indicator_end_value(indic, v)

#
# A meter with multiple arcs
#

meter = lv.meter(lv.scr_act())
meter.center()
meter.set_size(200, 200)

# Remove the circle from the middle
meter.remove_style(None, lv.PART.INDICATOR)

# Add a scale first
scale = meter.add_scale()
meter.set_scale_ticks(scale, 11, 2, 10, lv.palette_main(lv.PALETTE.GREY))
meter.set_scale_major_ticks(scale, 1, 2, 30, lv.color_hex3(0xeee), 10)
meter.set_scale_range(scale, 0, 100, 270, 90)

# Add a three arc indicator
indic1 = meter.add_arc(scale, 10, lv.palette_main(lv.PALETTE.RED), 0)
indic2 = meter.add_arc(scale, 10, lv.palette_main(lv.PALETTE.GREEN), -10)
indic3 = meter.add_arc(scale, 10, lv.palette_main(lv.PALETTE.BLUE), -20)

# Create an animation to set the value
a1 = lv.anim_t()
a1.init()
a1.set_values(0, 100)
a1.set_time(2000)
a1.set_repeat_delay(100)
a1.set_playback_delay(100)
a1.set_playback_time(500)
a1.set_var(indic1)
a1.set_repeat_count(lv.ANIM_REPEAT.INFINITE)
a1.set_custom_exec_cb(lambda a,val: set_value(indic1,val))
lv.anim_t.start(a1)

a2 = lv.anim_t()
a2.init()
a2.set_values(0, 100)
a2.set_time(1000)
a2.set_repeat_delay(100)
a2.set_playback_delay(100)
a2.set_playback_time(1000)
a2.set_var(indic2)
a2.set_repeat_count(lv.ANIM_REPEAT.INFINITE)
a2.set_custom_exec_cb(lambda a,val: set_value(indic2,val))
lv.anim_t.start(a2)

a3 = lv.anim_t()
a3.init()
a3.set_values(0, 100)
a3.set_time(1000)
a3.set_repeat_delay(100)
a3.set_playback_delay(100)
a3.set_playback_time(2000)
a3.set_var(indic3)
a3.set_repeat_count(lv.ANIM_REPEAT.INFINITE)
a3.set_custom_exec_cb(lambda a,val: set_value(indic3,val))
lv.anim_t.start(a3)

A clock from a meter¶

#include "../../lv_examples.h"
#if LV_USE_METER && LV_BUILD_EXAMPLES

static lv_obj_t * meter;

static void set_value(void * indic, int32_t v)
{
    lv_meter_set_indicator_end_value(meter, indic, v);
}

/**
 * A clock from a meter
 */
void lv_example_meter_3(void)
{
    meter = lv_meter_create(lv_scr_act());
    lv_obj_set_size(meter, 220, 220);
    lv_obj_center(meter);

    /*Create a scale for the minutes*/
    /*61 ticks in a 360 degrees range (the last and the first line overlaps)*/
    lv_meter_scale_t * scale_min = lv_meter_add_scale(meter);
    lv_meter_set_scale_ticks(meter, scale_min, 61, 1, 10, lv_palette_main(LV_PALETTE_GREY));
    lv_meter_set_scale_range(meter, scale_min, 0, 60, 360, 270);

    /*Create another scale for the hours. It's only visual and contains only major ticks*/
    lv_meter_scale_t * scale_hour = lv_meter_add_scale(meter);
    lv_meter_set_scale_ticks(meter, scale_hour, 12, 0, 0, lv_palette_main(LV_PALETTE_GREY));               /*12 ticks*/
    lv_meter_set_scale_major_ticks(meter, scale_hour, 1, 2, 20, lv_color_black(), 10);    /*Every tick is major*/
    lv_meter_set_scale_range(meter, scale_hour, 1, 12, 330, 300);       /*[1..12] values in an almost full circle*/

    LV_IMG_DECLARE(img_hand)

    /*Add a the hands from images*/
    lv_meter_indicator_t * indic_min = lv_meter_add_needle_img(meter, scale_min, &img_hand, 5, 5);
    lv_meter_indicator_t * indic_hour = lv_meter_add_needle_img(meter, scale_min, &img_hand, 5, 5);

    /*Create an animation to set the value*/
    lv_anim_t a;
    lv_anim_init(&a);
    lv_anim_set_exec_cb(&a, set_value);
    lv_anim_set_values(&a, 0, 60);
    lv_anim_set_repeat_count(&a, LV_ANIM_REPEAT_INFINITE);
    lv_anim_set_time(&a, 2000);     /*2 sec for 1 turn of the minute hand (1 hour)*/
    lv_anim_set_var(&a, indic_min);
    lv_anim_start(&a);

    lv_anim_set_var(&a, indic_hour);
    lv_anim_set_time(&a, 24000);    /*24 sec for 1 turn of the hour hand*/
    lv_anim_set_values(&a, 0, 60);
    lv_anim_start(&a);
}

#endif

#!//opt/bin/lv_micropython -i
import utime as time
import lvgl as lv
import display_driver
from imagetools import get_png_info, open_png

# Register PNG image decoder
decoder = lv.img.decoder_create()
decoder.info_cb = get_png_info
decoder.open_cb = open_png

# Create an image from the png file
try:
    with open('../../assets/img_hand_min.png','rb') as f:
        img_hand_min_data = f.read()
except:
    print("Could not find img_hand_min.png")
    sys.exit()

img_hand_min_dsc = lv.img_dsc_t({
  'data_size': len(img_hand_min_data),
  'data': img_hand_min_data
})

# Create an image from the png file
try:
    with open('../../assets/img_hand_hour.png','rb') as f:
        img_hand_hour_data = f.read()
except:
    print("Could not find img_hand_hour.png")
    sys.exit()

img_hand_hour_dsc = lv.img_dsc_t({
  'data_size': len(img_hand_hour_data),
  'data': img_hand_hour_data
})

def set_value(indic, v):
    meter.set_indicator_value(indic, v)
#
# A clock from a meter
#

meter = lv.meter(lv.scr_act())
meter.set_size(220, 220)
meter.center()

# Create a scale for the minutes
# 61 ticks in a 360 degrees range (the last and the first line overlaps)
scale_min = meter.add_scale()
meter.set_scale_ticks(scale_min, 61, 1, 10, lv.palette_main(lv.PALETTE.GREY))
meter.set_scale_range(scale_min, 0, 60, 360, 270)

# Create another scale for the hours. It's only visual and contains only major ticks
scale_hour = meter.add_scale()
meter.set_scale_ticks(scale_hour, 12, 0, 0, lv.palette_main(lv.PALETTE.GREY))  # 12 ticks
meter.set_scale_major_ticks(scale_hour, 1, 2, 20, lv.color_black(), 10)         # Every tick is major
meter.set_scale_range(scale_hour, 1, 12, 330, 300)                             # [1..12] values in an almost full circle

#    LV_IMG_DECLARE(img_hand)

# Add the hands from images
indic_min = meter.add_needle_img(scale_min, img_hand_min_dsc, 5, 5)
indic_hour = meter.add_needle_img(scale_min, img_hand_hour_dsc, 5, 5)

# Create an animation to set the value
a1 = lv.anim_t()
a1.init()
a1.set_values(0, 60)
a1.set_repeat_count(lv.ANIM_REPEAT.INFINITE)
a1.set_time(2000)        # 2 sec for 1 turn of the minute hand (1 hour)
a1.set_var(indic_min)
a1.set_custom_exec_cb(lambda a1,val: set_value(indic_min,val))
lv.anim_t.start(a1)

a2 = lv.anim_t()
a2.init()
a2.set_var(indic_hour)
a2.set_time(24000)       # 24 sec for 1 turn of the hour hand
a2.set_values(0, 60)
a2.set_custom_exec_cb(lambda a2,val: set_value(indic_hour,val))
lv.anim_t.start(a2)

Pie chart¶

#include "../../lv_examples.h"
#if LV_USE_METER && LV_BUILD_EXAMPLES

/**
 * Create a pie chart
 */
void lv_example_meter_4(void)
{
    lv_obj_t * meter = lv_meter_create(lv_scr_act());

    /*Remove the background and the circle from the middle*/
    lv_obj_remove_style(meter, NULL, LV_PART_MAIN);
    lv_obj_remove_style(meter, NULL, LV_PART_INDICATOR);

    lv_obj_set_size(meter, 200, 200);
    lv_obj_center(meter);

    /*Add a scale first with no ticks.*/
    lv_meter_scale_t * scale = lv_meter_add_scale(meter);
    lv_meter_set_scale_ticks(meter, scale, 0, 0, 0, lv_color_black());
    lv_meter_set_scale_range(meter, scale, 0, 100, 360, 0);

    /*Add a three arc indicator*/
    lv_coord_t indic_w = 100;
    lv_meter_indicator_t * indic1 = lv_meter_add_arc(meter, scale, indic_w, lv_palette_main(LV_PALETTE_ORANGE), 0);
    lv_meter_set_indicator_start_value(meter, indic1, 0);
    lv_meter_set_indicator_end_value(meter, indic1, 40);

    lv_meter_indicator_t * indic2 = lv_meter_add_arc(meter, scale, indic_w, lv_palette_main(LV_PALETTE_YELLOW), 0);
    lv_meter_set_indicator_start_value(meter, indic2, 40);  /*Start from the previous*/
    lv_meter_set_indicator_end_value(meter, indic2, 80);

    lv_meter_indicator_t * indic3 = lv_meter_add_arc(meter, scale, indic_w, lv_palette_main(LV_PALETTE_DEEP_ORANGE), 0);
    lv_meter_set_indicator_start_value(meter, indic3, 80);  /*Start from the previous*/
    lv_meter_set_indicator_end_value(meter, indic3, 100);
}

#endif

#
# Create a pie chart
#

meter = lv.meter(lv.scr_act())

# Remove the background and the circle from the middle
meter.remove_style(None, lv.PART.MAIN)
meter.remove_style(None, lv.PART.INDICATOR)

meter.set_size(200, 200)
meter.center()

# Add a scale first with no ticks.
scale = meter.add_scale()
meter.set_scale_ticks(scale, 0, 0, 0, lv.color_black())
meter.set_scale_range(scale, 0, 100, 360, 0)

# Add a three arc indicator*
indic_w = 100
indic1 = meter.add_arc(scale, indic_w,lv.palette_main(lv.PALETTE.ORANGE), 0)
meter.set_indicator_start_value(indic1, 0)
meter.set_indicator_end_value(indic1, 40)

indic2 = meter.add_arc(scale, indic_w, lv.palette_main(lv.PALETTE.YELLOW), 0)
meter.set_indicator_start_value(indic2, 40)  # Start from the previous
meter.set_indicator_end_value(indic2, 80)

indic3 = meter.add_arc(scale, indic_w, lv.palette_main(lv.PALETTE.DEEP_ORANGE), 0)
meter.set_indicator_start_value(indic3, 80)  # Start from the previous
meter.set_indicator_end_value(indic3, 100)

API¶

Typedefs

typedef uint8_t lv_meter_indicator_type_t¶

Enums

Values:

enumerator LV_METER_INDICATOR_TYPE_NEEDLE_IMG¶

enumerator LV_METER_INDICATOR_TYPE_NEEDLE_LINE¶

enumerator LV_METER_INDICATOR_TYPE_SCALE_LINES¶

enumerator LV_METER_INDICATOR_TYPE_ARC¶

enum lv_meter_draw_part_type_t¶

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

Values:

enumerator LV_METER_DRAW_PART_ARC¶: The arc indicator

enumerator LV_METER_DRAW_PART_NEEDLE_LINE¶: The needle lines

enumerator LV_METER_DRAW_PART_NEEDLE_IMG¶: The needle images

enumerator LV_METER_DRAW_PART_TICK¶: The tick lines and labels

Functions

lv_obj_t *lv_meter_create(lv_obj_t *parent)¶

Create a Meter object

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

lv_meter_scale_t *lv_meter_add_scale(lv_obj_t *obj)¶

Add a new scale to the meter.

Note

Indicators can be attached to scales.

Parameters: obj -- pointer to a meter object
Returns: the new scale

void lv_meter_set_scale_ticks(lv_obj_t *obj, lv_meter_scale_t *scale, uint16_t cnt, uint16_t width, uint16_t len, lv_color_t color)¶

Set the properties of the ticks of a scale

Parameters

obj -- pointer to a meter object
scale -- pointer to scale (added to meter)
cnt -- number of tick lines
width -- width of tick lines
len -- length of tick lines
color -- color of tick lines

void lv_meter_set_scale_major_ticks(lv_obj_t *obj, lv_meter_scale_t *scale, uint16_t nth, uint16_t width, uint16_t len, lv_color_t color, int16_t label_gap)¶

Make some "normal" ticks major ticks and set their attributes. Texts with the current value are also added to the major ticks.

Parameters

obj -- pointer to a meter object
scale -- pointer to scale (added to meter)
nth -- make every Nth normal tick major tick. (start from the first on the left)
width -- width of the major ticks
len -- length of the major ticks
color -- color of the major ticks
label_gap -- gap between the major ticks and the labels

void lv_meter_set_scale_range(lv_obj_t *obj, lv_meter_scale_t *scale, int32_t min, int32_t max, uint32_t angle_range, uint32_t rotation)¶

Set the value and angular range of a scale.

Parameters

obj -- pointer to a meter object
scale -- pointer to scale (added to meter)
min -- the minimum value
max -- the maximal value
angle_range -- the angular range of the scale
rotation -- the angular offset from the 3 o'clock position (clock-wise)

lv_meter_indicator_t *lv_meter_add_needle_line(lv_obj_t *obj, lv_meter_scale_t *scale, uint16_t width, lv_color_t color, int16_t r_mod)¶

Add a needle line indicator the scale

Parameters

obj -- pointer to a meter object
scale -- pointer to scale (added to meter)
width -- width of the line
color -- color of the line
r_mod -- the radius modifier (added to the scale's radius) to get the lines length

Returns

the new indicator

lv_meter_indicator_t *lv_meter_add_needle_img(lv_obj_t *obj, lv_meter_scale_t *scale, const void *src, lv_coord_t pivot_x, lv_coord_t pivot_y)¶

Add a needle image indicator the scale

Note

the needle image should point to the right, like -O----->

Parameters

obj -- pointer to a meter object
scale -- pointer to scale (added to meter)
src -- the image source of the indicator. path or pointer to lv_img_dsc_t
pivot_x -- the X pivot point of the needle
pivot_y -- the Y pivot point of the needle

Returns

the new indicator

lv_meter_indicator_t *lv_meter_add_arc(lv_obj_t *obj, lv_meter_scale_t *scale, uint16_t width, lv_color_t color, int16_t r_mod)¶

Add an arc indicator the scale

Parameters

obj -- pointer to a meter object
scale -- pointer to scale (added to meter)
width -- width of the arc
color -- color of the arc
r_mod -- the radius modifier (added to the scale's radius) to get the outer radius of the arc

Returns

the new indicator

lv_meter_indicator_t *lv_meter_add_scale_lines(lv_obj_t *obj, lv_meter_scale_t *scale, lv_color_t color_start, lv_color_t color_end, bool local, int16_t width_mod)¶

Add a scale line indicator the scale. It will modify the ticks.

Parameters

obj -- pointer to a meter object
scale -- pointer to scale (added to meter)
color_start -- the start color
color_end -- the end color
local -- tell how to map start and end color. true: the indicator's start and end_value; false: the scale's min max value
width_mod -- add this the affected tick's width

Returns

the new indicator

void lv_meter_set_indicator_value(lv_obj_t *obj, lv_meter_indicator_t *indic, int32_t value)¶

Set the value of the indicator. It will set start and and value to the same value

Parameters

obj -- pointer to a meter object
indic -- pointer to an indicator
value -- the new value

void lv_meter_set_indicator_start_value(lv_obj_t *obj, lv_meter_indicator_t *indic, int32_t value)¶

Set the start value of the indicator.

Parameters

obj -- pointer to a meter object
indic -- pointer to an indicator
value -- the new value

void lv_meter_set_indicator_end_value(lv_obj_t *obj, lv_meter_indicator_t *indic, int32_t value)¶

Set the start value of the indicator.

Parameters

obj -- pointer to a meter object
indic -- pointer to an indicator
value -- the new value

Variables

const lv_obj_class_t lv_meter_class¶

struct lv_meter_scale_t¶

Public Members

lv_color_t tick_color¶

uint16_t tick_cnt¶

uint16_t tick_length¶

uint16_t tick_width¶

lv_color_t tick_major_color¶

uint16_t tick_major_nth¶

uint16_t tick_major_length¶

uint16_t tick_major_width¶

int16_t label_gap¶

int16_t label_color¶

int32_t min¶

int32_t max¶

int16_t r_mod¶

uint16_t angle_range¶

int16_t rotation¶

struct lv_meter_indicator_t¶

Public Members

lv_meter_scale_t *scale¶

lv_meter_indicator_type_t type¶

lv_opa_t opa¶

int32_t start_value¶

int32_t end_value¶

const void *src¶

lv_point_t pivot¶

struct lv_meter_indicator_t needle_img¶

uint16_t width¶

int16_t r_mod¶

lv_color_t color¶

struct lv_meter_indicator_t needle_line¶

struct lv_meter_indicator_t arc¶

int16_t width_mod¶

lv_color_t color_start¶

lv_color_t color_end¶

uint8_t local_grad¶

struct lv_meter_indicator_t scale_lines¶

union lv_meter_indicator_t type_data¶

struct lv_meter_t¶

Public Members

lv_obj_t obj¶

lv_ll_t scale_ll¶

lv_ll_t indicator_ll¶