/**
  * Is this node closed in this tree?
  * @param FOLDER $node
  * @return boolean
  * @access private
  */
 public function closed($node)
 {
     if (!isset($this->open_nodes) || !sizeof($this->open_nodes)) {
         return $node->id != $this->app->root_folder_id;
     }
     return parent::closed($node);
 }