1.分模块
刚拿到一个项目时，要先想好一个项目可以分为几部分，每一部分怎么规划。这里我们按照最终想要的效果，主要分为四部分，分别为
2.理清楚层次关系
大的App组件中有myHeader,myList,myFooter组件，然后myList组件中包含myItem组件。
3.代码展示
src/App.vue
<template>
<div id="root">
<div class="todo-container">
<div class="todo-wrap">
<myHeader :addTodo="addTodo" />
<myList :todos="todos" :checkTodo="checkTodo" :deleteTodo="deleteTodo" />
<myFooter :todos="todos" :checkAllTodo="checkAllTodo" :clearAllTodo="clearAllTodo" />
</div>
</div>
</div>
</template>
<script>
import myHeader from './components/myHeader.vue';
import myFooter from './components/myFooter.vue';
import myList from './components/myList.vue';
export default {
name: 'App',
components: {
myHeader,
myList,
myFooter
},
data() {
return {
todos: [
{ id: '001', title: '学习python框架', done: false },
{ id: '002', title: 'vue知识点回顾', done: false },
{ id: '003', title: '英语PPT制作', done: false },
]
}
},
methods: {
//添加一个todo
addTodo(todoObj) {
this.todos.unshift(todoObj)
},
//勾选or取消勾选一个todo
checkTodo(id) {
this.todos.forEach((todo) => {
if (todo.id === id) todo.done = !todo.done
})
},
//删除一个todo
deleteTodo(id) {
this.todos = this.todos.filter(todo => todo.id !== id)
},
//全选or取消勾选
checkAllTodo(done) {
this.todos.forEach(todo => todo.done = done)
},
//删除已完成的todo
clearAllTodo() {
this.todos = this.todos.filter(todo => !todo.done)
}
}
}
</script>
<style>
body {
background: #fff;
}
.btn {
display: inline-block;
padding: 4px 12px;
margin-bottom: 0;
font-size: 14px;
line-height: 20px;
text-align: center;
vertical-align: middle;
cursor: pointer;
box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.2), 0 1px 2px rgba(0, 0, 0, 0.05);
border-radius: 4px;
}
.btn-danger {
color: #fff;
background-color: #da4f49;
border: 1px solid #bd362f;
}
.btn-danger:hover {
color: #fff;
background-color: #bd362f;
}
.btn:focus {
outline: none;
}
.todo-container {
width: 600px;
margin: 0 auto;
}
.todo-container .todo-wrap {
padding: 10px;
border: 1px solid #ddd;
border-radius: 5px;
}
</style>
src/myHeader.vue
<template>
<div class="todo-header">
<input type="text" placeholder="请输入你的任务名称，按回车键确认" @keyup.enter="add" v-model="title" />
</div>
</template>
<script>
import { nanoid } from 'nanoid'
export default {
name: 'myHeader',
props: ['addTodo'],
data() {
return {
title: ''
}
},
methods: {
// trim去掉前后空格
add() {
if (!this.title.trim()) return
const todoObj = { id: nanoid(), title: this.title, done: false }
this.addTodo(todoObj)
this.title = ''
}
}
}
</script>
<style scoped>
.todo-header input {
width: 560px;
height: 28px;
font-size: 14px;
border: 1px solid #ccc;
border-radius: 4px;
padding: 4px 7px;
}
.todo-header input:focus {
outline: none;
border-color: rgba(82, 168, 236, 0.8);
box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075), 0 0 8px rgba(82, 168, 236, 0.6);
}
</style>src/myList.vue
<template>
<ul class="todo-main">
<myItem v-for="todo in todos" :key="todo.id" :todo="todo" :checkTodo="checkTodo" :deleteTodo="deleteTodo" />
</ul>
</template>
<script>
import myItem from './myItem.vue';
export default {
name: 'myList',
components: {
myItem
},
props: ['todos', 'checkTodo', 'deleteTodo']
}
</script>
<style scoped>
.todo-main {
margin-left: 0px;
border: 1px solid #ddd;
border-radius: 2px;
padding: 0px;
}
.todo-empty {
height: 40px;
line-height: 40px;
border: 1px solid #ddd;
border-radius: 2px;
padding-left: 5px;
margin-top: 10px;
}
</style>src/myItem.vue
<template>
<li>
<label>
<input type="checkbox" :checked="todo.done" @click="handleCheck(todo.id)" />
<span>{
{ todo.title }}</span>
</label>
<button class="btn btn-danger" @click="handleDelete(todo.id, todo.title)">删除</button>
</li>
</template>
<script>
export default {
name: 'myItem',
props: ['todo', 'checkTodo', 'deleteTodo'],
methods: {
handleCheck(id) {
this.checkTodo(id)
},
handleDelete(id, title) {
if (confirm("确定删除任务：" + title + "吗？")) {
this.deleteTodo(id)
}
}
}
}
</script>
<style scoped>
li {
list-style: none;
height: 36px;
line-height: 36px;
padding: 0 5px;
border-bottom: 1px solid #ddd;
}
li label {
float: left;
cursor: pointer;
}
li label li input {
vertical-align: middle;
margin-right: 6px;
position: relative;
top: -1px;
}
li button {
float: right;
display: none;
margin-top: 3px;
}
li:before {
content: initial;
}
li:last-child {
border-bottom: none;
}
li:hover {
background-color: #eee;
}
li:hover button {
display: block;
}
</style>src/myFooter.vue
<template>
<div class="todo-footer" v-show="total">
<label>
<input type="checkbox" v-model="isAll" />
</label>
<span>
<span>已完成{
{ doneTotal }}</span> / 全部{
{ total }}
</span>
<button class="btn btn-danger" @click="clearAll">清除已完成任务</button>
</div>
</template>
<script>
export default {
name: 'myFooter',
props: ['todos', 'checkAllTodo', 'clearAllTodo'],
// 计算属性，将函数结果返回到模板语法中 reduce是es6知识点
computed: {
doneTotal() {
return this.todos.reduce((pre, todo) => pre + (todo.done ? 1 : 0), 0)
// let i=0
// this.todos.forEach(todo => {
// if (todo.done) i++
// })
// return i
},
total() {
return this.todos.length
},
isAll: {
get() {
return this.total === this.doneTotal && this.total > 0
},
set(value) {
this.checkAllTodo(value)
}
}
},
methods: {
clearAll() {
this.clearAllTodo()
}
}
}
</script>
<style scoped>
.todo-footer {
height: 40px;
line-height: 40px;
padding-left: 6px;
margin-top: 5px;
}
.todo-footer label {
display: inline-block;
margin-right: 20px;
cursor: pointer;
}
.todo-footer label input {
position: relative;
top: -1px;
vertical-align: middle;
margin-right: 5px;
}
.todo-footer button {
float: right;
margin-top: 5px;
}
</style>main.js
import Vue from 'vue'
import App from './App.vue'
Vue.config.productionTip = false
new Vue({
render: h => h(App),
}).$mount('#app')
4.运行结果展示
在vscode终端输入npm run serve，就得到了本地的一个网址
上面的代码有些方法和函数不太熟的朋友可以查MDN网站哦，上面都有详细的教程和介绍，链接如下：
https://developer.mozilla.org/zh-CN/
5.总结
（1）采用组件嵌套，这个学起来较为简单，只要将要展示的内容，层次结构理清楚。
（2）学习props传数据，让组件接收外部传过来的数据
（3）
-
props适用于：- 父组件 ==> 子组件 通信
- 子组件 ==> 父组件 通信（要求父组件先给子组件一个函数）