yarn add mitt

npm install --save mitt

// 標(biāo)準(zhǔn)的ES模塊化引入方式
import mitt from 'mitt'

const app = createApp(App)

// vue3.x的全局實例，要掛載在config.globalProperties上
app.config.globalProperties.$EventBus = new mitt()

import mitt from 'mitt'
export default new mitt()

import EventBus from '/common/EventBus.js'

/*
 * App.vue
 */
// setup中沒有this，需要通過getCurrentInstance來獲取Vue實例
import { getCurrentInstance } from 'vue'
import { Mp3Player } from '/common/Mp3Player.js'

export default {
  setup(){
    // ctx等同于Vue2.x的this
    const { ctx } = getCurrentInstance()
    
    // 監(jiān)聽-如果有新任務(wù)則播放音效
    ctx.$EventBus.on('newTask', data => {
      Mp3Player.play()
    })

    // 也可以通過*監(jiān)聽所有任務(wù)
    ctx.$EventBus.on('*', data => {
      console.log('EventBus come in', data)
    })
  }
}


/*
 * Control.vue
 */
// 判斷有新任務(wù)時，觸發(fā)
ctx.$EventBus.emit('newTask', data)

import {
    onBeforeUnmount,
    getCurrentInstance
  } from 'vue'

export default {
  setup(){
    const { ctx } = getCurrentInstance()

    onBeforeUnmount(() => {
      // 移除指定事件
      ctx.$EventBus.off('newTask')

      // 移除全部事件
      ctx.$EventBus.all.clear()
    })
  }
}