Flutter Bindings as Signals

[rodydavis]

When working with Flutter there are a lot of common callbacks and values that are used like AppLifecyleState, Frame callbacks and accessibility settings.

signals_flutter could provide the common signals to be used in the app:

void main() {
  final widgetsBinding = WidgetsBinding.instance;
  final schedulerBinding = SchedulerBinding.instance;

  final onFrame = signal<Duration>(Duration.zero);
  final onScheduleFrame = signal<Duration>(Duration.zero);
  final timings = listSignal<FrameTiming>([]);
  final appLifecycle = signal<AppLifecycleState>(AppLifecycleState.resumed);
  final accessibilityFocus = widgetsBinding.accessibilityFocus.toSignal();

  schedulerBinding
    ..addPersistentFrameCallback(onFrame.set)
    ..addTimingsCallback(timings.set)
    ..scheduleFrameCallback(onScheduleFrame.set, rescheduling: false);

  widgetsBinding
      .addObserver(AppLifecycleListener(onStateChange: appLifecycle.set));

  effect(() {
    print('on new frame: $onFrame');
  });

  effect(() {
    print('on schedule frame: $onScheduleFrame');
  });

  effect(() {
    print('on timings: $timings');
  });

  effect(() {
    print('accessibilityFocus: $accessibilityFocus');
  });
}