public function addToGroup($notificationKeyName, $notificationKey, array $registrationIds)
    {
        $request = new GroupRequest(self::ADD, $notificationKeyName, $notificationKey, $registrationIds);
        $response = $this->client->request('post', $this->url, $request->build());

        return $this->getNotificationToken($response);
    }
public function addToGroup($notificationKeyName, $notificationKey, array $registrationIds)
    {
        $request = new GroupRequest(self::ADD, $notificationKeyName, $notificationKey, $registrationIds);
        $response = $this->client->request('post', $this->url, $request->build());

        return $this->getNotificationToken($response);
    }
public function addToGroup ( $ notificationKeyName , $ notificationKey , array $ registrationIds ) { $ request = new GroupRequest ( self :: ADD , $ notificationKeyName , $ notificationKey , $ registrationIds ) ; $ response = $ this -> client -> request ( 'post' , $ this -> url , $ request -> build ( ) ) ; return $ this -> getNotificationToken ( $ response ) ; }
add registrationId to a existing group.

@param       $notificationKeyName
@param       $notificationKey
@param array $registrationIds     registrationIds to add
@return null|string notification_key
add registrationId to a existing group .