Starting app only if its not currently running

Question

I am sending push notification to users which when clicking on it opens the app.

My problem is that when the app is already open, clicking on the notification start

Answer 1

notificationIntent.addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP|Intent.FLAG_ACTIVITY_CLEAR_TOP|Intent.FLAG_ACTIVITY_NEW_TASK );

notificationIntent.putExtras(bundle);
PendingIntent pintent = PendingIntent.getActivity(context, 0, notificationIntent, PendingIntent.FLAG_UPDATE_CURRENT);