ElementUI tree 懒加载 手动刷新数据

<el-tree :props="props" :load="loadNode" lazy>el-tree>

loadNode(node, resolve) {
	 //加载数据的方法里把node，reslove存起来
      this.node = node;
      this.resolve = resolve;
 	 // 把子节点清空，否则下次加载时会直接往里push子节点导致重复
      this.node.childNodes = [];
     
      this.$http.get({
        url: url,
        successCallback: res => {
          resolve(res.data);
        },
        failCallback: res => {
          console.log(res);
        }
      });
   },
   refreshData(){
   //手动调用加载数据方法
   this.loadNode(this.node,this.reslove);
   }