# onPlatformBrightnessChanged property

VoidCallback onPlatformBrightnessChanged

A callback that is invoked whenever platformBrightness changes value.

The framework invokes this callback in the same zone in which the callback was set.

See also:

- `WidgetsBindingObserver`, for a mechanism at the widgets layer to observe when this callback is invoked.

## Implementation

    VoidCallback get onPlatformBrightnessChanged => _onPlatformBrightnessChanged;

void onPlatformBrightnessChanged= (VoidCallback callback)

## Implementation

    set onPlatformBrightnessChanged(VoidCallback callback) {
      _onPlatformBrightnessChanged = callback;
      _onPlatformBrightnessChangedZone = Zone.current;
    }