62 lines
2.1 KiB
Markdown
62 lines
2.1 KiB
Markdown
```eval_rst
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.. include:: /header.rst
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:github_url: |github_link_base|/widgets/linemeter.md
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```
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# Line meter (lv_lmeter)
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## Overview
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The Line meter object consists of some radial lines which draw a scale. Setting a value for the Line meter will change the color of the scale lines proportionally.
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## Parts and Styles
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The Line meter has only a main part, called `LV_LINEMETER_PART_MAIN`. It uses all the typical background properties the draw a rectangle-like or circle background and the *line* and *scale* properties to draw the scale lines.
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The active lines (which are related to smaller values the the current value) are colored from *line_color* to *scale_grad_color*. The lines in the end (after the current value) are set to *scale_end_color* color.
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## Usage
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### Set value
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When setting a new value with `lv_linemeter_set_value(linemeter, new_value)` the proportional part of the scale will be recolored.
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### Range and Angles
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The `lv_linemeter_set_range(linemeter, min, max)` function sets the range of the line meter.
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You can set the angle of the scale and the number of the lines by: `lv_linemeter_set_scale(linemeter, angle, line_num)`.
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The default angle is 240 and the default line number is 31.
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### Angle offset
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By default the scale angle is interpreted symmetrically to the y axis. It results in "standing" line meter. With `lv_linemeter_set_angle_offset` an offset can be added the scale angle.
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It can used e.g to put a quarter line meter into a corner or a half line meter to the right or left side.
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### Mirror
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By default the Line meter's lines are activated clock-wise. It can be changed using `lv_linemeter_set_mirror(linemeter, true/false)`.
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## Events
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Only the [Generic events](../overview/event.html#generic-events) are sent by the object type.
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Learn more about [Events](/overview/event).
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## Keys
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No *Keys* are processed by the object type.
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Learn more about [Keys](/overview/indev).
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## Example
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```eval_rst
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.. include:: /lv_examples/src/lv_ex_widgets/lv_ex_linemeter/index.rst
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```
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## API
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```eval_rst
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.. doxygenfile:: lv_linemeter.h
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:project: lvgl
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```
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