protected static function getGrid($args, $node, $auth)
 {
     $r = call_user_func(array(self::$called_class, 'getHeaderHTML'), $args);
     $r .= parent::getGrid($args, $node, $auth);
     $r .= call_user_func(array(self::$called_class, 'getTrailerHTML'), $args);
     return $r;
 }