过渡(动画)
1. 简介
Vue 在插入、更新或者移除 DOM 时，提供多种不同方式的应用过渡效果
本质上还是使用CSS3动画：transition、animation
2. 基本用法
使用transition组件，将要执行动画的元素包含在该组件内
<transition>
运动的元素
</transition>
过滤的CSS类名：6个
3. 钩子函数
8个
@before-enter="beforeEnter"
@enter="enter"
@after-enter="afterEnter"
@before-leave="beforeLeave"
@leave="leave"
@after-leave="afterLeave"
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>vue</title>
<script src="https://unpkg.com/vue"></script>
<style> p{
width: 300px;
height: 300px;
background-color:red;
}
.fade-enter-active,.fade-leave-active{
transition:all 3s ease;
}
.fade-enter-active{
opacity:1;
width:300px;
height:300px;
}
.fade-leave-active{
opacity:0;
width:50px;
height:50px;
}
/* .fade-enter需要放在.fade-enter-active的后面 */
.fade-enter{
opacity:0;
width: 100px;
height: 100px;
} </style> </head> <body> <div id="itany">
<button @click="flag=!flag">点我</button> <transition name="fade"
@before-enter="beforeEnter"
@enter="enter"
@after-enter="afterEnter"
@before-leave="beforeLeave"
@leave="leave"
@after-leave="afterLeave"
>
<p v-show="flag">网博</p>
</transition>
</div> <script>
var vm=new Vue({
el:'#itany',
data:{
flag:false
},
methods:{
beforeEnter(el){
// alert('动画进入之前');
},
enter(){
// alert('动画进入');
},
afterEnter(el){
// alert('动画进入之后');
el.style.background='blue';
},
beforeLeave(){
// alert('动画即将之前');
},
leave(){
// alert('动画离开');
},
afterLeave(el){
// alert('动画离开之后');
el.style.background='red';
}
}
});
</script> </body> </html>
4. 结合第三方动画库animate..css一起使用（https://daneden.github.io/animate.css/）
<transition enter-active-class="animated fadeInLeft" leave-active-class="animated fadeOutRight">
<p v-show="flag">网博</p>
</transition>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>vue</title>
<link rel="stylesheet" href="css/animate.css">
<script src="https://unpkg.com/vue"></script>
<script> window.onload = function(){ var vm = new Vue({
el:'#app',
data:{
flag:false
}
}) } </script> <style>
p{
width: 300px;
height: 300px;
background-color: red;
margin:0 auto;
}
</style> </head> <body> <div id="app">
<button @click="flag=!flag">点我</button> <transition enter-active-class="animated rollIn" leave-active-class="animated rollOut">
<p v-show="flag">网博</p>
</transition>
</div> </body> </html>
5. 多元素动画
<transition-group>
<transition-group enter-active-class="animated bounceInLeft" leave-active-class="animated bounceOutLeft">
<p v-show="flag" :key="1">你好</p>
<p v-show="flag" :key="2">世界</p>
</transition-group>
6. 练习
多元素动画
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>vue</title>
<link rel="stylesheet" href="css/animate.css">
<script src="https://unpkg.com/vue"></script>
<script> window.onload = function(){ var vm = new Vue({
el:'#app',
data:{
flag:true,
arr:['tom','jack','mike','alice','alex','mark'],
name:''
},
/* 计算属性 */
computed:{
arr2:function(){
var temp=[];
this.arr.forEach(val => {
if(val.includes(this.name)){
temp.push(val);
}
});
return temp;
}
}
}) } </script> <style>
p{
width: 50px;
height: 50px;
background-color: red;
margin:0 auto;
}
</style> </head> <body> <div id="app">
<input type="text" v-model="name">
<transition-group enter-active-class="animated bounceInLeft" leave-active-class="animated bounceOutRight">
<p v-for="(v,k) in arr2" :key="k">
{{v}}
</p>
</transition-group>
</div> </body> </html>