Ext.tree.TreeLoader=function(a){this.baseParams={};Ext.apply(this,a);this.addEvents("beforeload","load","loadexception");Ext.tree.TreeLoader.superclass.constructor.call(this)};Ext.extend(Ext.tree.TreeLoader,Ext.util.Observable,{uiProviders:{},clearOnLoad:true,load:function(a,b){if(this.clearOnLoad){while(a.firstChild){a.removeChild(a.firstChild)}}if(this.doPreload(a)){if(typeof b=="function"){b()}}else{if(this.dataUrl||this.url){this.requestData(a,b)}}},doPreload:function(d){if(d.attributes.children){if(d.childNodes.length<1){var c=d.attributes.children;d.beginUpdate();for(var b=0,a=c.length;b