move(node, type) {
      const data = node.data
      const parent = node.parent
      const children = parent.childNodes
      const index = children.findIndex(d => d.data.id === data.id)
      // 被移动的节点
      const element = children[index]
      if (type === 'up') {
        if (index === 0) {
          this.$message.warning('已经在首位了')
          return
        }
        // 参照节点
        const referenceNode = children[index - 1]
        this.$refs.tree.remove(element)
        this.$refs.tree.insertBefore(element.data, referenceNode)
      } else if (type === 'down') {
        if (index === children.length - 1) {
          this.$message.warning('已经在末尾了')
          return
        }
        const referenceNode = children[index + 1]
        this.$refs.tree.remove(element)
        this.$refs.tree.insertAfter(element.data, referenceNode)
      }
    },