CupertinoSwitch class

An iOS-style switch.

Used to toggle the on/off state of a single setting.

The switch itself does not maintain its toggle state. Instead, when the toggle state of the switch changes, the widget calls the onChanged callback. Most widgets that use a switch will listen for the onChanged callback and rebuild the switch with a new value to update the visual appearance of the switch.

MergeSemantics(
  child: CupertinoListTile(
    title: const Text('Lights'),
    trailing: CupertinoSwitch(
      value: _lights,
      onChanged: (bool value) { setState(() { _lights = value; }); },
    ),
    onTap: () { setState(() { _lights = !_lights; }); },
  ),
)

See also:

• Switch, the Material Design equivalent.
• developer.apple.com/design/human-interface-guidelines/toggles/