Ext.tree.Panel

initComponent : function() {

var data = null;
Ext.Ajax.request({
url : 'xxx/xx',
method : 'GET',
async:false,
//params:{pid:this.pj},
success : function(response, opts) {
var respText = Ext.JSON.decode(response.responseText);
data = respText.data;
}
});
TreePanel.root = data;

}