elementui tree控件 设置默认选中并高亮第一行

currentNodekey: "", //默认选中的节点树


async treeByDept() {
      await treeByDept({}).then((res) => {
        this.architectureData = res.data;
      
        if (this.architectureData.length > 0) {
          this.currentNodekey = this.architectureData[0].id;
          this.$nextTick(() => {
            this.$refs.treeRef.setCurrentKey(this.currentNodekey); //一定要加这个选中了否则样式没有出来
           });
          
        }
      });
    },