didChangeAppLifecycleState method
Called when the system puts the app in the background or returns the app to the foreground.
An example of implementing this method is provided in the class-level documentation for the WidgetsBindingObserver class.
This method exposes notifications from SystemChannels.lifecycle.
See also:
- AppLifecycleListener, an alternative API for responding to application lifecycle changes.
Implementation
@mustCallSuper
@override
void didChangeAppLifecycleState(AppLifecycleState state) {
  super.didChangeAppLifecycleState(state);
  logDebug("生命周期更新: $state");
  appLifecycleState = state;
  switch (state) {
    case AppLifecycleState.resumed:
      appIsForeground = true;
      break;
    case AppLifecycleState.inactive:
      break;
    case AppLifecycleState.paused:
      appIsForeground = false;
      break;
    case AppLifecycleState.detached:
      break;
    case AppLifecycleState.hidden:
      break;
  }
}