extjs4无法获取json文件中带url参数的数据

{children:[
{id:'01',text:'报表管理',children:[
{id:'01-01',url:'mainPage.jsp?v=',text:'网运报表',leaf:true},
{id:'01-02',text:'数据统计报表',children:[
{id:'01-02-01',url:'mainPage.jsp?v=',text:'b01-02-01',leaf:true},
{id:'01-02-02',url:'mainPage.jsp?v=',text:'a01-02-02',leaf:true}
]},
{id:'01-03',url:'mainPage.jsp?v=',text:'b01-03',leaf:true}
]},
{id:'02',url:'mainPage.jsp?v=',text:'b02',leaf:true}
]}//这个为treeReport.json

var treeStore1 = Ext.create('Ext.data.TreeStore', {
autoLoad : true,
proxy: {
type: 'ajax',
url: '../data/treeReport.json',
reader: {
type: 'json',
root: 'children'
//record: 'node'
}
},
sorters: [{
property: 'leaf',
direction: 'ASC'
}],
root: {
nodeType: 'async',
text: 'Ext JS',
//id: '00',
expanded: true
}
});


var treepanel2 = Ext.create('Ext.tree.Panel', {
//title: '简单的树形组件',
store: treeStore1,
animate:true,
autoScroll:true, //如果超出范围带自动滚动条
width: 500,
height:400,
border:true, //显示tree side frame
//数据容器
//loader:new Ext.tree.TreeLoader({url:"web/MenuTree.json"}),
rootVisible: true, //是否显示根节点
// renderTo: Ext.getBody()
containerScroll:true,
listeners: {
'itemclick': function (view, record) {
var leaf = record.get('leaf');
if (leaf) {
alert(record.get('url'));
var id = record.get('id');//id能获取到
var url = record.get('url');//url不能获取
var text = record.get('text');//text也能获取
alert("url=="+url+"id="+id+"text"+text);

var tabPanel = Ext.getCmp('MAINPANEL');
openWithTabPanel(id,url,text);
}
else {
alert('not leaf!');
var expand = record.get('expanded')
if (expand) {
view.collapse(record);
}
else {
view.expand(record);
}
}
}
} //listeners -------funcation end----------
});

请大侠帮我看看怎么才能获取到这个json数据

extjs4 json
[解决办法]
url不是TreeStore的默认列，所以通过get方法获取不到，要定义url列才行，否则要通过record.raw.url获取

var treeStore1 = Ext.create('Ext.data.TreeStore', {
autoLoad: true,
fields:['id','text','url'],
proxy: {