public function getUserGroupNames() {
        $groupNames= array();
        $id = $this->get('id') ? (string) $this->get('id') : '0';
        if (isset($_SESSION["modx.user.{$id}.userGroupNames"]) && $this->xpdo->user->get('id') == $this->get('id')) {
            $groupNames= $_SESSION["modx.user.{$id}.userGroupNames"];