Refreshing activity on receiving gcm push notification

Question

Update: GCM is deprecated, use FCM

How to refresh activity on receiving gcm push notification<

Answer 1

Intent notificationIntent = new Intent(context, MainActivity.class);
notificationIntent.setAction(Long.toString(System.currentTimeMillis()));
PendingIntent.getActivity(context, 0, notificationIntent, PendingIntent.FLAG_UPDATE_CURRENT);