code: public void hold() {
      notificationListener = null;
      setAppForeground(false);
      if (onMessageReceiverRegistered) {
        try {
          appContext.unregisterReceiver(onMessage);
        } catch (Exception e) {
          logger.warn("MFPPush:hold() - Exception while unregistering receiver. " + e.getMessage());
        }
        onMessageReceiverRegistered = false;
      }
    }
docs: Request MFPPush to stop delivering incoming push messages to
  notificationListener.onReceive() method. After hold(), MFPPush will store
  the latest push message in private shared preference and deliver that
  message during the next {@link #listen(MFPPushNotificationListener)}.
  <p/>
  This method is typically called from the onPause() method of the activity
  that is handling push notifications.