form加载后台JSON数据，不显示

js中相关定义如下：
[code="js"][/code]
//form中 items项定义
items : [ {
xtype : 'hidden',
name : 'userId'
}, {
xtype : 'hidden',
name : 'userName'
}, {
xtype : 'textfield',
fieldLabel : '门店名称',
name : 'storeName',
allowBlank : 'false',
width : '200'
}, {
xtype : 'textarea',
fieldLabel : '门店描述',
name : 'description',
allowBlank : 'true',
width : '200'
} ]

var userRecord = Ext.data.Record.create([ {
    name : 'userId'
}, {
    name : 'storeName'
}, {
    name : 'password'
}, {
    name : 'description'
} ]);

function loadData() {
    updateStoreForm.form.reader = new Ext.data.JsonReader({
        totalProperty : 'totalCount',
        root : 'result'
    }, userRecord);
    updateStoreForm.form.load({
        waitMsg : '请稍后...',
        waitTitle : '提示',
        url : 'loginUser.do'
    });
}

后台JSON数据：
{"totalCount":1,"result":{"description":"","password":"admin","storeName":"管理员","userId":"admin"}}

这样子为什么form加载不出JSON数据呢？

查看 Ext.form.Action.Submit api以及源码
[code="java"]/**

@class Ext.form.Action.Load
@extends Ext.form.Action
A class which handles loading of data from a server into the Fields of an {@link Ext.form.BasicForm}.
Instances of this class are only created by a {@link Ext.form.BasicForm Form} when
{@link Ext.form.BasicForm#load load}ing.
Response Packet Criteria
A response packet must contain:
success property : Boolean
data property : Object
The data property contains the values of Fields to load.
The individual value object for each Field is passed to the Field's
{@link Ext.form.Field#setValue setValue} method.
JSON Packets
By default, response packets are assumed to be JSON, so for the following form load call:

a success response packet may look like this:

{
success: true,
data: {
clientName: "Fred. Olsen Lines",
portOfLoading: "FXT",
portOfDischarge: "OSL"
}
}

while a failure response packet may look like this:

{
success: false,
errorMessage: "Consignment reference not found"
}
[/code]

以及源码中：
[code="java"]Ext.extend(Ext.form.Action.Load, Ext.form.Action, {
// private
type : 'load',

// private
run : function(){
    Ext.Ajax.request(Ext.apply(
            this.createCallback(this.options), {
                method:this.getMethod(),
                url:this.getUrl(false),
                headers: this.options.headers,
                params:this.getParams()
    }));
},

// private
success : function(response){
    var result = this.processResponse(response);
    if(result === true || !result.success || !result.data){
        this.failureType = Ext.form.Action.LOAD_FAILURE;
        this.form.afterAction(this, false);
        return;
    }
    this.form.clearInvalid();
    this.form.setValues(result.data);//这里可以看出取得是data
    this.form.afterAction(this, true);
},

.....
[/code]

json格式不对
[{"description":"","password":"admin","storeName":"管理员","userId":"admin"}]

非后台数据格式问题

采用form的load方式加载数据表单控件必须用id,所以他在搜索控件时搜不到，所以设置不上值。
但是有办法解决不设置id属性值解决办法参考：http://man1900.iteye.com/blog/773769

var userRecord = Ext.data.Record.create([ {
name : 'userId', type: 'string
}, {
name : 'storeName', type: 'string
}, {
name : 'password', type: 'string
}, {
name : 'description', type: 'string
} ]);

{"totalCount":1,"result":[{"description":"","password":"admin","storeName":"管理员","userId":"admin"}]}

function loadData() {
updateStoreForm.form.reader = new Ext.data.JsonReader({
totalProperty : 'totalCount',
root : 'result'
}, userRecord);
updateStoreForm.form.load({
waitMsg : '请稍后...',
waitTitle : '提示',
url : 'loginUser.do'
});
}
因为你这样写的
totalProperty : 'totalCount',
root : 'result'定
所以后台返回应该这样
{"totalCount":1,"result":[{"description":"","password":"admin","storeName":"管理员","userId":"admin"}]}

Ext.form.Action.Load的 API文档开头就说明了响应数据包必须类似下面的格式：

{ success: true, data: { clientName: "Fred. Olsen Lines", portOfLoading: "FXT", portOfDischarge: "OSL" } }