Android onNotificationPosted is called twice for gmail and whatsApp

Question

I know this looks like a duplicate of Android NotificationListenerService onNotificationPosted fire twice and NotificationListenerService onNotificationPosted() called multiple times for single Notification when it is part of grouped notification, but I have tried their solutions and they don't seem to work.

All I want to do is to have a background service that is counting the number of notifications a person gets on the phone and then just write that into a text file.

It works fine for SMS and Hangout notifications (i.e. it is fired only once for each notification) but when I test it using WhatsApp and Gmail, it gets fired twice and so, for each Gmail notification, I have two rows in my text file.

Here is my code. Any help will be appreciated.

public class NotifCounterService extends NotificationListenerService {

   public static String TAG = NotifCounterService.class.getSimpleName();

   Date dateStart;

   private Logger logger;

   private Context mContext;

   @Override
   public void onCreate() {
      Log.d(TAG, "Created");

      logger = new Logger(TAG);
      mContext = getApplicationContext();
   }

   @Override
   public IBinder onBind(Intent intent) {
      return super.onBind(intent);
   }

   @Override
   public void onNotificationPosted(StatusBarNotification sbn) {

      Log.d(TAG, "Notification has arrived");

      Log.d(TAG, "ID: " + sbn.getId() + " Posted by: " + sbn.getPackageName() + " at: " + sbn.getPostTime() + " ");

      logger.i(sbn.getId() + "," + sbn.getPackageName() + "," + sbn.getPostTime(), mContext);
      logger.close();

      /*
       * Log.i(TAG, "ID:" + sbn.getId()); Log.i(TAG, "Posted by:" +
       * sbn.getPackageName()); Log.i(TAG, "tickerText:" +
       * sbn.getNotification().tickerText);
       */

      /*
       * for (String key : sbn.getNotification().extras.keySet()) { Log.i(TAG, key +
       * "=" + sbn.getNotification().extras.get(key).toString()); }
       */

   }
}

Answer 1

This happens because WhatsApp and Gmail send a group summary notification alongside other notifications.

The related flag is documented here: https://developer.android.com/reference/android/app/Notification.html#FLAG_GROUP_SUMMARY

You can ignore notifications with this flag like this:

   @Override
   public void onNotificationPosted(StatusBarNotification sbn) {
          if ((sbn.getNotification().flags & Notification.FLAG_GROUP_SUMMARY) != 0) {
                  //Ignore the notification
                  return;
          }

          //...
   }