element UI对el-dropdown的二次封装（三级下拉框）

<template>
  <el-dropdown trigger="click" :hide-on-click="true">
    <el-button>
      <svg-icon
        :icon-class="iconClass"
        class-name="icon-svg"
      />
      <span>{
   {
    text }}</span>
      <i class="el-icon-arrow-down el-icon--right" />
    </el-button>
    <el-dropdown-menu slot="dropdown">
      <template v-for="item1 in menu">
        <el-dropdown-item v-if="!item1.childer" :key="item1.title" @click.native=