didStopListening method Null safety

  1. @override
void didStopListening()
override

Called when the number of listeners changes from one to zero.

Implementation

@override
void didStopListening() {
  first.removeListener(_maybeNotifyListeners);
  first.removeStatusListener(_maybeNotifyStatusListeners);
  next.removeListener(_maybeNotifyListeners);
  next.removeStatusListener(_maybeNotifyStatusListeners);
}