gistfile1.json

var datasource = [{
    "text": "null",//根节点
    "expanded": true,
    "items": [
        {
            "text":"user1",//第一个子菜单
            "expanded": true,
            "items":[
                {
                    "text":"user2",//二级菜单
                    "expanded": true,
                    "items":[
                        {
                            "text":"user4",//三级
                            "items":[
                                {
                                "text":"user5"//四级
                                }
                            ]
                        }
                    ]
                },
                {
                    "text":"user3",
                }
            ]
        },
    ]
}];