父页面

<template>
  <div>
    <el-button type="primary" @click="visible = true">展示弹窗</el-button>
    <!-- 弹窗组件 -->
    <PlayVideo v-if="visible" :visible.sync='visible' />
  </div>
</template>

<script>
import PlayVideo from './playVideo.vue'
export default {
  data () {
    return {
      visible: false
    }
  },
  components: {
    PlayVideo
  }
}
</script>

<style>
</style>

子组件

<template>
  <div>
    <el-dialog class="dialog" :visible.sync="visible" title="标题" :before-close="handleClose">
      22222
    </el-dialog>
  </div>
</template>

<script>
export default {
  props: {
    visible: {
      default: false
    }
  },
  methods: {
    // 取消
    handleClose () {
      this.$emit('update:visible', false)
    }
  }
}
</script>

<style>
</style>