[Flutter/dart] The method at notification tapping does not work when the app is terminated

Phenomenon

Create a notification using flutter_local_notification. The method when tapping the notification is also registered.

If the app is up (whether foreground or background) when the notification comes, it works as expected.

However, if the app is terminated when the notification arrives, tapping the notification will not result in the registered operation.

Cause and solution

The registered method will disappear when the application is terminated (reference).

Note: from version 4.0 of the plugin, calling initialize will not trigger the onSelectNotification callback when the application was started by tapping on a notification to trigger. Use the getNotificationAppLaunchDetails method that is available in the plugin if you need to handle a notification triggering the launch for an app e.g. change the home route of the app for deep-linking.

As a countermeasure, a method called getNotificationAppLaunchDetails () tells you whether the app was started by a notification tap, so if it starts from a notification tap, you can perform the desired action.

NotificationAppLaunchDetails _lanuchDeatil
=await flutterLocalNotificationsPlugin.launchedFromNotification();

if (_lanuchDeatil!=null){
    if (_lanuchDeatil.didNotificationLaunchApp){
      if (_lanuchDeatil.payload==null){

      }
      else {
        ・・・         
      }
    }
  }
}

If _lanuchDeatil.didNotificationLaunchApp is true, it is started by a notification tap, so perform what you want. At that time, _lanuchDeatil.payload contains the payload passed when creating the notification, so refer to it.