keep-alive缓存离开时的高度

keep-alive

<keep-alive include="HelloWorld" exclude="detail">
        <router-view></router-view>
 </keep-alive>
        //给想缓存的列表套上盒子
<div class="content" ref='box'>
      <ul>
        <li v-for="(item,index) in list" :key="index">
            {{item.name}}
        </li>
      </ul>
 </div>

activated(){
    console.log('进入了');
    this.$refs.box.scrollTop=this.scrollY;
  },
  deactivated(){
    console.log('离开了');
    console.log(this.scrollY)
    this.scrollY=this.$refs.box.scrollTop;
  }

//设置style
.content{
  flex: 1;
  height: 100%;
  overflow: scroll;
}