2.1 KiB
Bar (lv_bar)
Overview
The bar object has a background and an indicator on it. The width of the indicator is set according to the current value of the bar.
Vertical bars can be created if the width of the object is smaller than its height.
Not only the end, but also the start value of the bar can be set, which changes the start position of the indicator.
Parts and Styles
LV_PART_MAIN
The background of the bar and it uses the typical background style properties. Adding padding makes the indicator smaller or larger. Theanim_time
style property sets the animation time if the values set withLV_ANIM_ON
.LV_PART_INDICATOR
The indicator itself; also uses all the typical background properties.
Usage
Value and range
A new value can be set by lv_bar_set_value(bar, new_value, LV_ANIM_ON/OFF)
.
The value is interpreted in a range (minimum and maximum values) which can be modified with lv_bar_set_range(bar, min, max)
.
The default range is 0..100.
The new value in lv_bar_set_value
can be set with or without an animation depending on the last parameter (LV_ANIM_ON/OFF
).
Modes
The bar can be one of the following modes:
LV_BAR_MODE_NORMAL
A normal bar as described aboveLV_BAR_MODE_SYMMETRICAL
Draw the indicator from the zero value to current value. Requires a negative minimum range and positive maximum range.LV_BAR_MODE_RANGE
Allows setting the start value too bylv_bar_set_start_value(bar, new_value, LV_ANIM_ON/OFF)
. The start value always has to be smaller than the end value.
Events
LV_EVENT_DRAW_PART_BEGIN
andLV_EVENT_DRAW_PART_END
are sent for the following parts:LV_BAR_DRAW_PART_INDICATOR
The indicator of the barpart
:LV_PART_INDICATOR
draw_area
: area of the indicatorrect_dsc
See the events of the Base object too.
Learn more about Events.
Keys
No Keys are processed by the object type.
Learn more about Keys.
Example
.. include:: ../../../examples/widgets/bar/index.rst
API
.. doxygenfile:: lv_bar.h
:project: lvgl