<!-- 主组件 -->
<view class="_root {{selectable?'_select':''}}" style="{{containerStyle}}">
  <!-- 加载完成前显示自定义 loading -->
  <slot wx:if="{{!nodes[0]}}" />
  <!-- 节点树 -->
  <node id="_root" childs="{{nodes}}" opts="{{[lazyLoad,loadingImg,errorImg,showImgMenu,selectable]}}" mp-weixin:mp-qq:mp-baidu:catchadd="_add" mp-alipay:onAdd="_add" />
</view>