pivotGrid的官方例子为什么显示不了数据
ext3.3，小弟刚接触学习pivotgrid，为什么examples里的例子运行的时候只显示grid的标题，leftAxis和topAxis显示不出的？
官方代码如下：
/*! * Ext JS Library 3.3.0 * Copyright(c) 2006-2010 Ext JS, Inc. * licensing@extjs.com * http://www.extjs.com/license */Ext.onReady(function() { var SaleRecord = Ext.data.Record.create([ {name: 'person', type: 'string'}, {name: 'product', type: 'string'}, {name: 'city', type: 'string'}, {name: 'state', type: 'string'}, {name: 'month', type: 'int'}, {name: 'quarter', type: 'int'}, {name: 'year', type: 'int'}, {name: 'quantity', type: 'int'}, {name: 'value', type: 'int'} ]); var myStore = new Ext.data.Store({ url: 'simple.json', autoLoad: true, reader: new Ext.data.JsonReader({ root: 'rows', idProperty: 'id' }, SaleRecord) }); var pivotGrid = new Ext.grid.PivotGrid({ title : 'PivotGrid example', width : 800, height : 259, renderTo : 'docbody', store : myStore, aggregator: 'sum', measure : 'value', viewConfig: { title: 'Sales Performance' }, leftAxis: [ { width: 80, dataIndex: 'person' }, { width: 90, dataIndex: 'product' } ], topAxis: [ { dataIndex: 'year' }, { dataIndex: 'city' } ] });});