# Switch (lv_switch) (/widgets/switch)



Overview [#overview]

Switch Widgets look like little sliders and are used to display, and optionally
modify, a value that can be "on" or "off".

By default, a Switch is oriented horizontally. Its orientation will be vertical
if you set `width` \< `height`.

Parts and Styles [#parts-and-styles]

* <ApiLink name="LV_PART_MAIN" /> Switch's background; uses the [typical
  background style properties](/common-widget-features/styles/overview). `padding` makes the indicator smaller
  in the respective direction.
* <ApiLink name="LV_PART_INDICATOR" /> The indicator that shows the current state of
  the Switch; also uses the [typical background style properties](/common-widget-features/styles/overview).
* <ApiLink name="LV_PART_KNOB" /> A rectangle (or circle) drawn at the left or right
  side of the indicator; also uses the [typical background style properties](/common-widget-features/styles/overview) to modify the knob's appearance. By default, the knob is round
  (radius-style can modify this) with diameter slightly smaller than the smaller
  side of the slider.  The knob can be made larger with the `padding` values.
  Padding values can be asymmetric as well.

Usage [#usage]

Change state [#change-state]

The Switch uses the standard <ApiLink name="LV_STATE_CHECKED" /> state.

To get the current state of the Switch (with `true` being ON), use
<ApiLink name="lv_obj_has_state" display="lv_obj_has_state(widget, LV_STATE_CHECKED)" />.

Call <ApiLink name="lv_obj_add_state" display="lv_obj_add_state(widget, LV_STATE_CHECKED)" /> to turn it on, or
<ApiLink name="lv_obj_remove_state" display="lv_obj_remove_state(widget, LV_STATE_CHECKED)" /> to turn it off
programmatically.

Change orientation [#change-orientation]

With a Switch is created, its default orientation is
<ApiLink name="LV_SWITCH_ORIENTATION_AUTO" />, which causes it to be oriented based
on `width` and `height`.  You can change this behavior using
<ApiLink name="lv_switch_set_orientation" display="lv_switch_set_orientation(widget, orientation)" />.  Possible values for
`orientation` are:

* <ApiLink name="LV_SWITCH_ORIENTATION_AUTO" />
* <ApiLink name="LV_SWITCH_ORIENTATION_HORIZONTAL" />
* <ApiLink name="LV_SWITCH_ORIENTATION_VERTICAL" />

Events [#events]

* <ApiLink name="LV_EVENT_VALUE_CHANGED" /> Sent when Switch changes state.

<Callout type="info" title="Further Reading">
  Learn more about [Events](/common-widget-features/events) emitted by all Widgets.

  Learn more about [events](/common-widget-features/events).
</Callout>

Keys [#keys]

* `LV_KEY_UP/RIGHT` Turns Switch ON
* `LV_KEY_DOWN/LEFT` Turns Switch OFF
* <ApiLink name="LV_KEY_ENTER" /> Toggles the Switch

<Callout type="info" title="Further Reading">
  Learn more about [Keys](/main-modules/indev/keypad).
</Callout>

Examples [#examples]

Simple Switch [#simple-switch]

<LvglExample name="lv_example_switch_1" path="widgets/switch/lv_example_switch_1" />

Switch Orientation [#switch-orientation]

<LvglExample name="lv_example_switch_2" path="widgets/switch/lv_example_switch_2" />

API [#api]