Wrapper around Google's VisibilityDetector for combining it with Flutter's WidgetsBindingObserver in order to achieve Android's onResume/onPause and iOS's viewDidAppear/viewDidDisappear on Flutter.

How Does it Work?

A FocusDetector widget takes in a child and optional onFocusGained/onFocusLost callbacks and fires those as the widget's focus changes. Some cases that trigger the focus change:

  1. When the widget is first created;
  2. When its route is popped back to;
  3. When the app is sent to background/foreground while the widget is visible;


Bringing onResume/viewDidAppear onPause/viewDidDisappear to Flutter


Check out the focus-detector/set-state-focus-detector or focus-detector/bloc-focus-detector branch of the Breaking Bapp repository.