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超轻量级php框架startmvc

vue.js实现备忘录功能的方法

更新时间:2020-05-23 17:12:01 作者:startmvc
这个vue实现备忘录的功能demo是K在github上找到的,K觉得这是一个用来对vue.js入门的一个非常

这个vue实现备忘录的功能demo是K在github上找到的,K觉得这是一个用来对vue.js入门的一个非常简单的demo,所以拿在这里共享一下。

(尊重他人劳动成果,从小事做起~  demo原github地址:https://github.com/vuejs/vue)

一、实现效果

 

二、代码展示


<!DOCTYPE html>
<html>

 <head>
 <meta charset="UTF-8">
 <title>备忘录</title>
 <link rel="stylesheet" type="text/css" href="css/index.css" rel="external nofollow" />
 <style>[v-cloak] { display: none; }</style>
 </head>

 <body>
 <section class="todoapp">
 <header class="header">
 <h1>todos</h1>
 <input class="new-todo"
 autofocus autocomplete="off"
 placeholder="What needs to be done?"
 v-model="newTodo"
 @keyup.enter="addTodo">
 </header>
 <section class="main" v-show="todos.length" v-cloak>
 <input class="toggle-all" type="checkbox" v-model="allDone">
 <ul class="todo-list">
 <li v-for="todo in filteredTodos"
 class="todo"
 :key="todo.id"
 :class="{ completed: todo.completed, editing: todo == editedTodo }">
 <div class="view">
 <input class="toggle" type="checkbox" v-model="todo.completed">
 <label @dblclick="editTodo(todo)">{{ todo.title }}</label>
 <button class="destroy" @click="removeTodo(todo)"></button>
 </div>
 <input class="edit" type="text"
 v-model="todo.title"
 v-todo-focus="todo == editedTodo"
 @blur="doneEdit(todo)"
 @keyup.enter="doneEdit(todo)"
 @keyup.esc="cancelEdit(todo)">
 </li>
 </ul>
 </section>
 <footer class="footer" v-show="todos.length" v-cloak>
 <span class="todo-count">
 <strong>{{ todos.length }}</strong> {{ remaining | pluralize }} left
 </span>
 <ul class="filters">
 <li><a href="#/all" rel="external nofollow" :class="{ selected: visibility == 'all' }">All</a></li>
 <li><a href="#/active" rel="external nofollow" :class="{ selected: visibility == 'active' }">Active</a></li>
 <li><a href="#/completed" rel="external nofollow" :class="{ selected: visibility == 'completed' }">Completed</a></li>
 </ul>
 <button class="clear-completed" @click="removeCompleted" v-show="todos.length > remaining">
 Clear completed
 </button>
 </footer>
 </section>
 <footer class="info">
 <p>双击编辑一条备忘录</p>
 </footer>

 </body>

 <script language="JavaScript" src="js/director.js"></script>
 <script language="JavaScript" src="js/vue.js"></script>
 <script language="JavaScript" src="js/index_vue.js"></script>

</html>

// 本地缓存设置
// 防止页面关闭后,数据全部丢失的问题
var STORAGE_KEY = 'todos-vuejs-2.0'
var todoStorage = {
 
 // 获取本地存储中的内容
 fetch:function(){
 // JSON.parse()解析一个json字符串
 // localStorage.getItem 从本地存储中获取STORAGE_KEY字段的值
 var todos = JSON.parse(localStorage.getItem(STORAGE_KEY)||'[]');
 // foreach遍历todos,两个参数分别为遍历出的每一个子单元及对应的索引
 todos.forEach(function(todo,index){
 todo.id = index;
 })
 todoStorage.uid = todos.length;
 return todos;
 },
 
 // 保存时将内容写进本地存储
 save:function(todos){
 // localStorage.setItem 将todos转化成字符串存入本地存储,键名为STORAGE_KEY
 localStorage.setItem(STORAGE_KEY,JSON.stringify(todos))
 }
 
}

// 可视化状态过滤设置
// 包括全选(all)、选择未完成(active)、选择已完成(completed)
var filters = {
 all:function(todos){
 return todos;
 },
 
 // filter() 方法创建一个新的数组,新数组中的元素是通过检查指定数组中符合条件的所有元素。
 active:function(todos){
 return todos.filter(function(todo){
 return !todo.completed;
 })
 },
 
 completed:function(todos){
 return todos.filter(function(todo){
 return todo.completed;
 })
 }
}


// vue实例化
var app = new Vue({
 
 // data 参数设置
 data:{
 todos:todoStorage.fetch(),
 newTodo:'',
 editedTodo:null,
 visibility:'all'
 },
 
 // watch 监视todos在本地储存中的变化
 watch:{
 todos:{
 handler:function(todos){
 todoStorage.save(todos)
 },
 deep:true
 }
 },
 
 // computed 检测数据发生变动时执行函数
 computed:{
 
 filteredTodos:function(){
 return filters[this.visibility](this.todos)
 },
 
 remaining:function(){
 return filters.active(this.todos).length
 },
 
 allDone:{
 get:function(){
 return this.remaining === 0
 },
 
 set:function(value){
 this.todos.forEach(function(todo){
 todo.completed = value
 })
 }
 
 }
 },
 
 // methods 方法设置
 methods:{
 addTodo:function(){
 var value = this.newTodo && this.newTodo.trim()
 if(!value){
 return;
 }
 this.todos.push({
 id:todoStorage.uid++,
 title:value,
 completed:false
 })
 this.newTodo = ''
 },
 
 removeTodo:function(todo){
 this.todos.splice(this.todos.indexOf(todo),1)
 },
 
 editTodo:function(todo){
 this.beforeEditCache = todo.title;
 this.editedTodo = todo
 },
 
 doneEdit:function(todo){
 if(!this.editedTodo){
 return;
 };
 this.editedTodo = null;
 todo.title = todo.title.trim()
 if(!todo.title){
 this.removeTodo(todo)
 }
 },
 
 cancelEdit:function(todo){
 this.editedTodo = null;
 todo.title = this.beforeEditCache
 },
 
 removeCompleted:function(){
 this.todos = filters.active(this.todos)
 }
 },
 
 directives:{
 'todo-focus':function(el,binding){
 if(binding.value){
 el.focus()
 }
 }
 }
})


// hashchange URL的片段标识符更改触发
function onHashChange(){
 var visbility = window.location.hash.replace(/#\/?/, '');
 if(filters[visbility]){
 app.visibility = visbility
 }else{
 window.location.hash = '';
 app.visbility = 'all'
 }
}

window.addEventListener('hashchange',onHashChange)
onHashChange()

// mount 手动挂载
app.$mount('.todoapp')

以上这篇vue.js实现备忘录功能的方法就是小编分享给大家的全部内容了,希望能给大家一个参考,也希望大家多多支持脚本之家。

vue.js实现备忘录功能