详解VUE里子组件如何获取父组件动态变化的值

export default {
 name: 'SwitchButton',
 props: {
  status: {
   type: Boolean,
   default () {
    return false
   }
  }
 },
 data () {
  return {
   switchStatusData: this.status // 重新定义数据
  }
 },
 computed: {
  switchStatus: function () {
   return this.status // 直接监听props里的status状态
  }
 }
 }
}

export default {
 name: 'SwitchButton',
 props: {
  status: {
   type: Boolean,
   default () {
    return false
   }
  }
 },
 data () {
  return {
   switchStatusData: this.status
  }
 },
 computed: {
  switchStatus: function () {
   return this.switchStatusData // 监听switchStatusData 的变化
  }
 },
 watch: {
  status (newV, oldV) { // watch监听props里status的变化，然后执行操作
   console.log(newV, oldV)
   this.switchStatusData = newV
  }
 },
 methods: {
  switchHandleClick () {
   this.switchStatusData = !this.switchStatusData
   this.$emit('switchHandleClick', this.switchStatusData)
  }
 }
}

<template>
 <span class="switch-bar" :class="{'active': switchStatus}" @click="switchHandleClick"><span class="switch-btn"></span></span>
</template>
<script>
export default {
 name: 'SwitchButton',
 props: {
  status: {
   type: Boolean,
   default () {
    return false
   }
  }
 },
 data () {
  return {
   switchStatusData: this.status
  }
 },
 computed: {
  switchStatus: function () {
   return this.status
  }
 },
 // watch: {
 //  status (newV, oldV) {
 //   console.log(newV, oldV)
 //   this.switchStatusData = newV
 //  }
 // },
 methods: {
  switchHandleClick () {
   this.switchStatusData = !this.switchStatusData
   this.$emit('switchHandleClick', this.switchStatusData)
  }
 }
}
</script>
<style lang="stylus" scoped>
 @import "~styles/varibles.styl"
 .area-wrapper
  line-height: .8rem;
  padding: 0 .4rem;
  .switch
   float: right;
   font-size: 0;
  .switch-bar
   position: relative;
   display: inline-block;
   width: .8rem;
   height: .4rem;
   border-radius: .4rem;
   background: #ddd;
   border: 2px solid #ddd;
   vertical-align: middle;
   transition: background .3s, border .3s;
   &.active
    background: $bgColor;
    border: 2px solid $bgColor;
    .switch-btn
     left: .4rem;
     background: #fff;
  .switch-btn
   position: absolute;
   left: 0px;
   display: inline-block;
   width: .4rem;
   height: .4rem;
   border-radius: .2rem;
   background: #fff;
   transition: background .3s, left .3s;
</style>