子组件

<script lang="ts">
import { createComponent } from '@vue/composition-api'

export default createComponent({
  setup(props, {root}) {
    const action = (data) => {
      root.$emit('change', data)
    }

    return {
      action ,
    }
  },
})
</script>

父组件

<template>
    <my-component @change="change" />
</template

<script lang="ts">
import { createComponent } from '@vue/composition-api'
export default createComponent({
  setup(props, ctx) {
    const change = (data) => {
      console.log(data)
    }

    return {
      change ,
    }
  },
})
</script>

父组件一直接收不到子组件事件通知？