Extjs无法接收显示Struts后台数据
如题
后台使用的是SSH框架，前台想用Ext呈现后台数据，数据已经能正常获取，但是没有显示出来，不知道是哪里配错了，按着网上
http://www.blogjava.net/fuhoujun/archive/2008/10/02/232050.html       的步骤做的  JSP页面能显示数据如图

下面是代码
Struts逻辑代码：

public String execute()

	{

		List<Room> roomlist=roomService.findAllRoom();

		ServletActionContext.getRequest().setAttribute("roomlist", roomlist);

		

		System.out.println("查找完毕");

		this.setTotalCount(roomlist.size());

		JSONArray array=JSONArray.fromObject(roomlist);

		this.jsonString="{totalCount:"+this.getTotalCount()+",results:"+array.toString()+"}";

		/*return SUCCESS;*/

		System.out.println("转换完毕");

               return SUCCESS;

Struts.xml

<action name="listRoom" class="ListRoom">

         <result name="success"  type="json"/>

		 <param name="jsonString">/ext_form.jsp</param> 

            

       </action>

JS代码：

Ext.onReady(function(){

	Ext.define('Room',

	{

		extend:'Ext.data.Model',

		fields:[{

			name:'roomid',type:'int'

		},

		{

			name:'roomname',type:'string'

		},

		{

			name:'price',type:'int'

		},

		{

			name:'category',type:'string'

		},

		{name:'status',type:'int'}]

	});

	

	 var rd = new Ext.data.JsonReader({

                //总记录数

                totalProperty: 'totalCount', 

                //哪儿是数据的头，可以看action里面是怎么定义数据格式的，这里就是如何解析的           

                    root: 'results', 

                    id:'roomid',

                //有那些字段呢？

                fields:[

                      /*   {name:'roomid'},

                         {name:'roomname'},

                         {name:'price'},

                         {name:'category'},

                         {name:'status'},*/

                   &nb