android - How to know when my app has been killed?

Question

I need to know when the user kills my app (Force stop). I've been reading the android lifecycle, which has the onStop() and onDestroy() functions, these are related to each activity the user ends on my app, but not when the user forces stop or kills my app.

Is there any way to know when the user kills the app?

Answer 1

I have found one way to do this.....

1. Make one service like this

   public class OnClearFromRecentService extends Service {
   
       @Override
       public IBinder onBind(Intent intent) {
           return null;
       }
   
       @Override
       public int onStartCommand(Intent intent, int flags, int startId) {
           Log.d("ClearFromRecentService", "Service Started");
           return START_NOT_STICKY;
       }
   
       @Override
       public void onDestroy() {
           super.onDestroy();
           Log.d("ClearFromRecentService", "Service Destroyed");
       }
   
       @Override
       public void onTaskRemoved(Intent rootIntent) {
           Log.e("ClearFromRecentService", "END");
           //Code here
           stopSelf();
       }
   }
   

2. Register this service in Manifest.xml like this

   <service android:name="com.example.OnClearFromRecentService" android:stopWithTask="false" />
   

3. Then start this service on your splash activity

   startService(new Intent(getBaseContext(), OnClearFromRecentService.class));
   

And now whenever you will clear your app from android recent Then this method onTaskRemoved() will execute.

NOTE: In Android O+ this solution only works when the app is full-time in foreground. After more than 1 minute with the app in background, the OnClearFromRecentService (and all other Services running) will be automatically force-killed by the system so the onTaskRemoved() will not be executed.