<template>
  <div class="test">

    <div v-for="(item, index) in arr" :key="index">
      <p>姓名：{{ item.name }}</p>
      <p>年龄：{{ item.age }}</p>
      <p>爱好：{{ item.like }}</p>
    </div>
  </div>
</template>

<script>

import Vue from 'vue'

export default {
  data() {
    return {

      arr: [{ name: "蕾蕾", age: 23 }, { name: "佳佳", age: 20 }]
    };
  },
  created() {
    this.arr.forEach(res => {
setTimeout(()=>{   //此处模拟异步调数据
        res.like = "刷抖音";

         Vue.set(res,"like","刷抖音")

        
      })

    });
  }
};
</script>

此时页面是渲染不出来爱好的数据的，如图：

处理方法1：用Vue.set(蓝色部分)

处理方法2：数组改变用push

 data() {
    return {
      arr: [{ name: "蕾蕾", age: 23 }, { name: "佳佳", age: 20 }]
    };
  },

 created() {
    this.arr.forEach(res => {

          this.arr=[]
          setTimeout(()=>{
            res.like = "刷抖音";
            this.arr.push(res);
         })

    });
  }