BI.createWidget({
    type: "bi.custom_tree",
    el: {
        type: "bi.button_tree",
        chooseType: 0,
        layouts: [{
            type: "bi.vertical",
            hgap: 30
        }]
    },
    items: [{
               id: -1,
               pId: -2,
               value: "根目录",
               open: true,
               type: "bi.plus_group_node",
               height: 25
           },
           {
               id: 1,
               pId: -1,
               value: "第一级目录1",
               type: "bi.plus_group_node",
               height: 25
           },
           {
               id: 11,
               pId: 1,
               value: "第二级文件1",
               type: "bi.single_select_item",
               height: 25
           }]
});