样式没加只是功能可以！

<template>
  <div>
    <ul class="tab">
      <li v-for="(item,index) in ['活动','订单','详情']" :key="index"  @click="isActive =index">
        {{item}}
      </li>

    </ul>
    <div>
      <!-- <div v-if="isActive==0" >1111</div>
      <div v-if="isActive==1">22222</div>
      <div v-if="isActive==2">33333</div> -->
      <div  v-for="(item,index) in ['活动','订单','详情']" :key="index"  v-show="isActive==index">
        {{item}}
      </div>
    </div>
  </div>
</template>
<style lang="">
  .tab{float: left;width: 100%;}
  .tab>li{float: left;width: 33.33%;}

</style>

<script>
import axios from 'axios'

export default {
  data(){
    return {
      isActive:0,

    };
  },
  methods:{

  }
}
</script>