Vue.js 轮播组件

<template>
  <div class="slide-show" @mouseover="clearInv" @mouseout="runInv">
    <div class="slide-img">
      <a :href="slides[nowIndex].href">
        <transition name="slide-trans">
          <img v-if="isShow" :src="slides[nowIndex].src">
        </transition>
        <transition name="slide-trans-old">
          <img v-if="!isShow" :src="slides[nowIndex].src">
        </transition>
      </a>
    </div>
    <h2>{{ slides[nowIndex].title }}</h2>
    <ul class="slide-pages">
      <li @click="goto(prevIndex)"><</li>
      <li v-for="(item, index) in slides"
          @click="goto(index)"
      >
        <a :class="{on: index === nowIndex}">{{ index + 1 }}</a>
      </li>
      <li @click="goto(nextIndex)">></li>
    </ul>
  </div>
</template>

<script>
    export default {
      name: "slide",
      props:{
        slides:{
          type:Array,
          default:[]
        },
        inv:{
          type:[Number ,String],
          default: 1000
        }
      },
      data(){
        return {
          nowIndex:0,
          isShow:true
        }
      },
      computed:{
        prevIndex(){
          if(this.nowIndex == 0){
            return this.slides.length - 1
          }else{
            return this.nowIndex-1
          }
        },
        nextIndex(){
          if(this.nowIndex == this.slides.length - 1){
            return 0
          }else{
            return this.nowIndex+1
          }
        }
      },
      methods:{
        goto (index) {
          this.isShow = false
          setTimeout(() => {
            this.isShow = true
            this.nowIndex = index
          }, 10)
        },
        runInv () {
          this.invId = setInterval(() => {
            this.goto(this.nextIndex)
          }, this.inv)
        },
        clearInv () {
          clearInterval(this.invId)
        }
      },
      mounted(){
        this.runInv()
      }
    }
</script>

<style scoped>
  .slide-trans-enter-active {
    transition: all .5s;
  }
  .slide-trans-enter {
    transform: translateX(900px);
  }
  .slide-trans-old-leave-active {
    transition: all .5s;
    transform: translateX(-900px);
  }
  .slide-show {
    position: relative;
    margin: 15px 15px 15px 0;
    width: 900px;
    height: 500px;
    overflow: hidden;
  }
  .slide-show h2 {
    position: absolute;
    width: 100%;
    height: 100%;
    color: #fff;
    background: #000;
    opacity: .5;
    bottom: 0;
    height: 30px;
    text-align: left;
    padding-left: 15px;
  }
  .slide-img {
    width: 100%;
  }
  .slide-img img {
    width: 100%;
    position: absolute;
    top: 0;
  }
  .slide-pages {
    position: absolute;
    bottom: 10px;
    right: 15px;
  }
  .slide-pages li {
    display: inline-block;
    padding: 0 10px;
    cursor: pointer;
    color: #fff;
  }
  .slide-pages li .on {
    text-decoration: underline;
  }
</style>

　　《====================        计算属性：只有在它的相关依赖数据发生改变时，才会重新赋值       =======================》