生命周期
生命周期 & 生命周期四个阶段
Vue 生命周期函数
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<div id="app">
<h3>{{ title }}</h3>
<div>
<button @click="count--">-</button>
<span>{{ count }}</span>
<button @click="count++">+</button>
</div>
</div>
<script src="./vue.js"></script>
<script>
const app = new Vue({
el: '#app',
data: {
count: 100,
title: '计数器'
},
// 1. 创建阶段（准备数据）
beforeCreated(){
console.log('beforeCreated 响应式数据准备好之前',this.count);
},
created(){
console.log('created 响应式数据准备好之后',this.count);
// this.数据名 = 请求回来的数据
// 可以开始发送初始化渲染的请求了
},
// 2. 挂载阶段（渲染模板）
beforeMount(){
console.log('beforeMount 模板渲染之前',document.querySelector('h3').innerHTML)
},
mounted(){
console.log('mounted 模板渲染之后',document.querySelector('h3').innerHTML)
// 可以开始操作dom
},
// 3. 更新阶段
beforeUpdate(){
console.log('beforeUpdate 数据修改了，视图还没更新')
},
updated(){
console.log('updated 数据修改了，试图已经更新')
},
// 4. 卸载阶段
beforeDestory(){
console.log('beforeDestory，卸载前')
console.log('清除掉一些Vue以外的资源占用，定时器，延时器...')
},
destoryed(){
console.log('destoryed，卸载后')
}
})
</script>
</body>
</html>
案例
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<style>
* {
margin: 0;
padding: 0;
list-style: none;
}
.news {
display: flex;
height: 120px;
width: 600px;
margin: 0 auto;
padding: 20px 0;
cursor: pointer;
}
.news .left {
flex: 1;
display: flex;
flex-direction: column;
justify-content: space-between;
padding-right: 10px;
}
.news .left .title {
font-size: 20px;
}
.news .left .info {
color: #999999;
}
.news .left .info span {
margin-right: 20px;
}
.news .right {
width: 160px;
height: 120px;
}
.news .right img {
width: 100%;
height: 100%;
object-fit: cover;
}
</style>
</head>
<body>
<div id="app">
<ul>
<li v-for="(item,index) in list" :key="item.id" class="news">
<div class="left">
<div class="title">{{ item.title }}</div>
<div class="info">
<span>{{ item.source }}</span>
<span>{{ item.time }}</span>
</div>
</div>
<div class="right">
<img :src="item.img" alt="">
</div>
</li>
</ul>
</div>
<script src="./vue.js"></script>
<script src="./axios.js"></script>
<script>
// 接口地址：http://hmajax.itheima.net/api/news
// 请求方式：get
const app = new Vue({
el: '#app',
data: {
list:[]
},
async created(){
// 1. 发送请求 获取数据
const res = await axios.get('http://hmajax.itheima.net/api/news')
// 2. 将数据更新给 data 中的 list
this.list = res.data.data
}
})
</script>
</body>
</html>
<!DOCTYPE html>
<html lang="zh-CN">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>示例-获取焦点</title>
<!-- 初始化样式 -->
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/reset.css@2.0.2/reset.min.css">
<!-- 核心样式 -->
<style>
html,
body {
height: 100%;
}
.search-container {
position: absolute;
top: 30%;
left: 50%;
transform: translate(-50%, -50%);
text-align: center;
}
.search-container .search-box {
display: flex;
}
.search-container img {
margin-bottom: 30px;
}
.search-container .search-box input {
width: 512px;
height: 16px;
padding: 12px 16px;
font-size: 16px;
margin: 0;
vertical-align: top;
outline: 0;
box-shadow: none;
border-radius: 10px 0 0 10px;
border: 2px solid #c4c7ce;
background: #fff;
color: #222;
overflow: hidden;
box-sizing: content-box;
-webkit-tap-highlight-color: transparent;
}
.search-container .search-box button {
cursor: pointer;
width: 112px;
height: 44px;
line-height: 41px;
line-height: 42px;
background-color: #ad2a27;
border-radius: 0 10px 10px 0;
font-size: 17px;
box-shadow: none;
font-weight: 400;
border: 0;
outline: 0;
letter-spacing: normal;
color: white;
}
body {
background: no-repeat center /cover;
background-color: #edf0f5;
}
</style>
</head>
<body>
<div class="container" id="app">
<div class="search-container">
<img src="https://www.itheima.com/images/logo.png" alt="">
<div class="search-box">
<input type="text" v-model="words" id="inp">
<button>搜索一下</button>
</div>
</div>
</div>
<script src="./vue.js"></script>
<script>
const app = new Vue({
el: '#app',
data: {
words: ''
},
// 核心思路：
// 1. 等待输入框渲染出来
// 2. 让输入框获取焦点
mounted(){
document.querySelector('#inp').focus()
}
})
</script>
</body>
</html>
综合案例
饼图：https://echarts.apache.org/zh/index.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>Document</title>
<!-- CSS only -->
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@5.1.3/dist/css/bootstrap.min.css" />
<style>
.red {
color: red !important;
}
.search {
width: 300px;
margin: 20px 0;
}
.my-form {
display: flex;
margin: 20px 0;
}
.my-form input {
flex: 1;
margin-right: 20px;
}
.table> :not(:first-child) {
border-top: none;
}
.contain {
display: flex;
padding: 10px;
}
.list-box {
flex: 1;
padding: 0 30px;
}
.list-box a {
text-decoration: none;
}
.echarts-box {
width: 600px;
height: 400px;
padding: 30px;
margin: 0 auto;
border: 1px solid #ccc;
}
tfoot {
font-weight: bold;
}
@media screen and (max-width: 1000px) {
.contain {
flex-wrap: wrap;
}
.list-box {
width: 100%;
}
.echarts-box {
margin-top: 30px;
}
}
</style>
</head>
<body>
<div id="app">
<div class="contain">
<!-- 左侧列表 -->
<div class="list-box">
<!-- 添加资产 -->
<form class="my-form">
<input v-model.trim="name" type="text" class="form-control" placeholder="消费名称" />
<input v-model.number="price" type="text" class="form-control" placeholder="消费价格" />
<button @click="add" type="button" class="btn btn-primary">添加账单</button>
</form>
<table class="table table-hover">
<thead>
<tr>
<th>编号</th>
<th>消费名称</th>
<th>消费价格</th>
<th>操作</th>
</tr>
</thead>
<tbody>
<tr v-for="(item,index) in list" :key="item.id">
<td>{{ index+1 }}</td>
<td>{{ item.name }}</td>
<td :class="{red:item.price>500}">{{ item.price.toFixed(2) }}</td>
<td><a @click="del(item.id)" href="javascript:;">删除</a></td>
</tr>
</tbody>
<tfoot>
<tr>
<td colspan="4">消费总计： {{ total.toFixed(2) }}</td>
</tr>
</tfoot>
</table>
</div>
<!-- 右侧图表 -->
<div class="echarts-box" id="main"></div>
</div>
</div>
<script src="../echarts.min.js"></script>
<script src="../vue.js"></script>
<script src="../axios.js"></script>
<script>
/**
* 接口文档地址：
* https://www.apifox.cn/apidoc/shared-24459455-ebb1-4fdc-8df8-0aff8dc317a8/api-53371058
*
* 功能需求：
* 1. 基本渲染
* (1) 立刻发送请求获取数据 created
* (2) 拿到数据，存到data的响应式数据中
* (3) 结合数据，进行渲染 v-for
* (4) 消费统计 -> 计算属性
* 2. 添加功能
* (1) 收集表单数据 v-model
* (2) 给添加按钮注册点击事件，发送添加请求
* (3) 需要重新渲染
* 3. 删除功能
* (1) 注册点击事件，传参数 id
* (2) 根据 id 发送删除请求
* (3) 需要重新渲染
* 4. 饼图渲染
* (1) 初始化一个饼图 echarts mounted钩子实现
* (2) 根据数据时更新饼图
*/
const app = new Vue({
el: '#app',
data: {
list: [],
name: '',
price: ''
},
computed: {
total() {
return this.list.reduce((sum, item) => sum + item.price, 0)
}
},
created() {
// const res = await axios.get('https://applet-base-api-t.itheima.net/bill', {
// params: {
// creator: '小黑',
// name:'',
// price:''
// }
// })
// this.list = res.data.data
this.getList()
},
mounted() {
this.myChart = echarts.init(document.querySelector('#main'))
this.myChart.setOption({
// 大标题
title: {
text: '消费账单列表',
left: 'center'
},
// 提示框
tooltip: {
trigger: 'item'
},
// 图例
legend: {
orient: 'vertical',
left: 'left'
},
// 数据项
series: [
{
name: '消费账单',
type: 'pie',
radius: '50%', // 半径
data: [
// { value: 1048, name: '球鞋' },
// { value: 735, name: '防晒霜' }
],
emphasis: {
itemStyle: {
shadowBlur: 10,
shadowOffsetX: 0,
shadowColor: 'rgba(0, 0, 0, 0.5)'
}
}
}
]
})
},
methods: {
async getList() {
const res = await axios.get('https://applet-base-api-t.itheima.net/bill', {
params: {
creator: '小黑',
name: '',
price: ''
}
})
this.list = res.data.data
// 更新图表
this.myChart.setOption({
// 数据项
series: [
{
data: this.list.map(item => ({value:item.price,name:item.name}))
}
]
})
},
async add() {
if (!this.name) {
alert('请输入消费名称')
return
}
if (typeof this.price !== 'number') {
alert('请输入消费价格')
return
}
const res = await axios.post('https://applet-base-api-t.itheima.net/bill', {
creator: '小黑',
name: this.name,
price: this.price
})
// 重新渲染
this.getList()
this.name = ''
this.price = ''
},
async del(id) {
// 根据 id 发送删除请求
const res = await axios.delete(`https://applet-base-api-t.itheima.net/bill/${id}`)
// 重新渲染
this.getList()
}
}
})
</script>
</body>
</html>
工程化开发入门
工程化开发 & 脚手架 Vue CLI
脚手架目录文件介绍 & 项目运行流程
组件化开发 & 根组件
App.vue 文件（单文件组件）的三个组成部分
<template>
<div class="App">
<div class="box" @click="fn"></div>
</div>
</template>
<script>
// 导出的是当前组建的配置项
// 里面可以提供data（特殊） methods computed watch 生命周期
export default {
created(){
console.log('我是created')
},
methods:{
fn(){
alert('你好')
}
}
}
</script>
<style>
.App {
width: 400px;
height: 400px;
background-color: pink;
}
.App .box {
width: 100px;
height: 100px;
background-color: skyblue;
}
</style>
普通组件的注册使用
App.vue
<template>
<div class="App">
<!-- 头部组件 -->
<HmHeader></HmHeader>
<!-- 主体组件 -->
<HmMain></HmMain>
<!-- 底部组件 -->
<HmFooter></HmFooter>
</div>
</template>
<script>
import HmHeader from './components/HmHeader.vue'
import HmMain from './components/HmMain.vue'
import HmFooter from './components/HmFooter.vue'
export default {
components:{
HmHeader:HmHeader,
HmMain:HmMain,
HmFooter:HmFooter
}
}
</script>
<style>
.App {
width: 600px;
height: 700px;
background-color: #87ceeb;
margin: 0 auto;
padding: 20px;
}
</style>
<template>
<div class="hm-footer">
我是hm-footer
</div>
</template>
<script>
</script>
<style>
.hm-footer {
height: 100px;
line-height: 100px;
text-align: center;
font-size: 30px;
background-color: #4f81bd;
color: white;
}
</style>
<template>
<div class="hm-header">
我是hm-header
</div>
</template>
<script>
</script>
<style>
.hm-header {
height: 100px;
line-height: 100px;
text-align: center;
font-size: 30px;
background-color: #8064a2;
color: white;
}
</style>
<template>
<div class="hm-main">
我是hm-main
</div>
</template>
<script>
</script>
<style>
.hm-main {
height: 400px;
line-height: 100px;
text-align: center;
font-size: 30px;
background-color: #f79646;
color: white;
margin: 20px 0;
}
</style>
综合案例
