code: function (url, callback) {
  		var ajax = this.obj.$ajax;
  		if (this._update_busy)
  			return false;
  		else
  			this._update_busy = true;
  
  		//this._loader = this._loader || new dtmlXMLLoaderObject(true);
  
  		//this._loader.async=true;
  		//this._loader.waitCall=callback;
  		//this._loader.loadXML(url);
  		ajax.get(url, callback);
  
  	}
docs: /* sends query to the server and call callback function