extjs textField之后添加一个button以及后台数据交互

var pnRow1=new Ext.Panel({border:false,layout:'column',items:[new Ext.Panel({columnWidth:.2,layout:'form',border:false,labelWidth:100,labelAlign:'left',items:[{   xtype : "textfield",         id:"contract_id",      name:"contract_id",      maxLength :20,      value:'${model.contract_id}',             fieldLabel : "合同标识",             width : 150}]}),//new Ext.Panel({columnWidth:.1,layout:'form',border:false,labelWidth:100,labelAlign:'right',items:[{text: '获取',id:'selectDuty2',xtype: 'button',handler : function() {Ext.Ajax.request({url: 'contractAction!getContract_id.shtml',method: 'POST',params: {},success: function (result, request){Ext.getCmp('contract_id').setValue(result.responseText);//alert( result.responseText+"-----"+request["id"]);},failure: function (result, request){            }});}}]}), //new Ext.Panel({columnWidth:.3,layout:'form',border:false,labelWidth:100,labelAlign:'right',items:[comboInspaction_authority2]}), //new Ext.Panel({columnWidth:.3,layout:'form',border:false,labelWidth:100,labelAlign:'right',items:[comboInspection_type2]}) ]});