ExtJS4 如何从 JSON 设置 TreePanels 根节点

我想使用 ExtJS4 创建 TreePanel。所以我将 JSON 发送到代理阅读器，其格式如下

{
    "text": "en",
    "children": {
        "text": "/",
        "children": [{
                "text": "/page",
                "children": [{
                        "text": "/page/new",
                        "children": [],
                        "leaf": true,
                        "expanded": false
                    },
                    {
                        "text": "/page/remove",
                        "children": [],
                        "leaf": true,
                        "expanded": false
                    }
                ],
                "leaf": false,
                "expanded": false
            },
            {
                "text": "/home",
                "children": [],
                "leaf": true,
                "expanded": false
            }
        ],
        "leaf": false,
        "expanded": true
    }
}

如果需要，我该如何配置我的商店en节点作为我的根节点。

Ext.define('Example.store.WebItems', {
    extend: 'Ext.data.TreeStore',

    model: 'Example.model.Item',

    proxy: {
        type: 'ajax',
        api: {
            read: 'some/url',
        },
        reader: {
            type: 'json',
            root: 'children' // Is this correct?
        }
    },
    root: // What should I write here?
});

当我定义TreeStore的根为root: 'My Root'它将添加新的根，但我想使用定义的根JSON.

所以我的问题是：

1. 如何使用 JSON 中的根节点而不是手动定义它？
2. 我是否还必须在代理阅读器和 TreeStore 中定义根节点？

响应必须有root.

例如：

{
     MyRoot: {
         "text": "en",
         "children": {
             "text": "/",
             "children": [{
                 "text": "/page",
                 "children": [{
                     "text": "/page/new",
                     "children": [],
                     "leaf": true,
                     "expanded": false
                 }, {
                     "text": "/page/remove",
                     "children": [],
                     "leaf": true,
                     "expanded": false
                 }],
                 "leaf": false,
                 "expanded": false
             }, {
                 "text": "/home",
                 "children": [],
                 "leaf": true,
                 "expanded": false
             }],
             "leaf": false,
             "expanded": true
         }
     }
 }

在这个例子中root is MyRoot。现在你必须“告诉”读者你的root is MyRoot:

        // ...
        reader: {
            type: 'json',
            root: 'MyRoot'
        }
    },
    //root: this config is not needed now
});