Vue3.0 中切换页面时的过渡动画

<template>
  <div id="app">
    <router-view class="router-view" v-slot="{ Component }">
      <transition :name="transitionName">
        <component :is="Component" />
      </transition>
    </router-view>
  </div>
</template>

<script>
export default {
  data () {
    return {
      transitionName: 'slide-left'
    }
  },
  watch: {
    $route (to, from) {
      if (to.meta.index > from.meta.index) {
        this.transitionName = 'slide-left'
        console.log('slide-left')
      } else if (to.meta.index < from.meta.index) {
        this.transitionName = 'slide-right'
        console.log('slide-right')
      } else {
        this.transitionName = ''
      }
    }
  }
}
</script>

<style lang="stylus">
#app {
  height: 100%;
  font-family: 'Avenir', Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  color: #2c3e50;
}

.router-view{
    width: 100%;
    height: auto;
    position: absolute;
    top: 0;
    bottom: 0;
    margin: 0 auto;
    -webkit-overflow-scrolling: touch;
}

.slide-right-enter-active,
.slide-right-leave-active,
.slide-left-enter-active,
.slide-left-leave-active{
    height: 100%;
    will-change: transform;
    transition: all 500ms cubic-bezier(.55,0,.1,1);
    position: absolute;
    backface-visibility: hidden;
}
.slide-right-enter-active{
    opacity: 0;
    transform: translate3d(-100%, 0, 0);
}
.slide-right-leave-active{
    opacity: 0;
    transform: translate3d(100%, 0, 0);
}
.slide-left-enter-active{
    opacity: 0;
    transform: translate3d(100%, 0, 0);
}
.slide-left-leave-active{
    opacity: 0;
    transform: translate3d(-100%, 0, 0);
}
</style>

router中需要对页面mate设置index，用以判断向左向右滑动

[{
    path: '/myPage',
    name: 'MyPage',
    component: () => import('@/views/MyPage.vue'),
    meta: { index: 1 }
},
{
    path: '/mySecondPage',
    name: 'MySecondPage',
    component: () => import('@/views/MySecondPage.vue'),
    meta: { index: 2 }
}]