作用:非父子组件之间,进行简易消息传递。(复杂场景→ Vuex)
一、实现步骤
创建一个都能访问的事件总线 (空Vue实例) → utils/EventBus.js
叫事件总线的原因是因为本质是它俩消息的接受和发送是利用了Vue的事件机制
import Vue from 'vue' const Bus = new Vue() export default Bus
A组件(接受方),监听Bus的 $on事件
created () { // B组件通过触发事件传递了参数(发布消息),进而在A组件由于监听了这个消息,进而就会执行回调 Bus.$on('sendMsg', (msg) => { this.msg = msg }) }
B组件(发送方),触发Bus的$emit事件
Bus.$emit('sendMsg', '这是一个消息')
二、代码示例
EventBus.js
import Vue from 'vue'
const Bus = new Vue()
export default Bus
BaseA.vue(接受方)
<template>
<div class="base-a">
我是A组件(接受方)
<p>{{msg}}</p>
</div>
</template>
<script>
import Bus from '../utils/EventBus'
export default {
data() {
return {
msg: '',
}
},
created() {
Bus.$on('sendMsg', (msg) => {
// console.log(msg)
this.msg = msg
})
},
}
</script>
<style scoped>
.base-a {
width: 200px;
height: 200px;
border: 3px solid #000;
border-radius: 3px;
margin: 10px;
}
</style>
BaseB.vue(发送方)
<template>
<div class="base-b">
<div>我是B组件(发布方)</div>
<button @click="sendMsgFn">发送消息</button>
</div>
</template>
<script>
import Bus from '../utils/EventBus'
export default {
methods: {
sendMsgFn() {
Bus.$emit('sendMsg', '今天天气不错,适合旅游')
},
},
}
</script>
<style scoped>
.base-b {
width: 200px;
height: 200px;
border: 3px solid #000;
border-radius: 3px;
margin: 10px;
}
</style>
BaseC.vue(接收方)
<template>
<div class="base-c">
我是C组件(接受方)
<p>{{msg}}</p>
</div>
</template>
<script>
import Bus from '../utils/EventBus'
export default {
data() {
return {
msg: '',
}
},
created() {
Bus.$on('sendMsg', (msg) => {
// console.log(msg)
this.msg = msg
})
},
}
</script>
<style scoped>
.base-c {
width: 200px;
height: 200px;
border: 3px solid #000;
border-radius: 3px;
margin: 10px;
}
</style>
App.vue
<template>
<div class="app">
<BaseA></BaseA>
<BaseB></BaseB>
<BaseC></BaseC>
</div>
</template>
<script>
import BaseA from './components/BaseA.vue'
import BaseB from './components/BaseB.vue'
import BaseC from './components/BaseC.vue'
export default {
components:{
BaseA,
BaseB,
BaseC
}
}
</script>
<style>
</style>