el-tree设置默认选中checkbox且复选框值改变触发事件

checkedList(){
      this.$nextTick(() =>{
        let res = this.$refs.tree.getCheckedNodes(true)
        let ids = []
        res.forEach(item =>{
          ids.push(item.id)
        })
        this.checkIdList = ids.toString()
        this.initTable()
      });
    },
    //格式化模板
    renderContent(h, { node, data, store }){//每个父节点统计子节点数量方法
      if(data.sonNodeList !=''){
        return (
          
            {node.label+'（'+data.sonNodeList.length+'）'}
          
        );
      }else{
        return (
          
            {node.label}
          
        );
      }
    },
    async initLeftMenu(){
      let res = await getCatalogue(this.type)
      if(res.code == 0){
        this.treeData = res.data[this.type]
      }
      this.loading = false
      // 初始化复选框选中状态
      this.treeData.forEach((i, n) => {
        i.sonNodeList.forEach((index,node) =>{
          this.$nextTick(() =>{
          var node = this.$refs.tree.getNode(index)
          if (node.isLeaf) {
            this.$refs.tree.setChecked(node, true)
          }
        });
        })
      })
    },