vue css动画原理

从隐藏到显现

从显现到隐藏

 1 <!DOCTYPE html>
 2 <html>
 3     <head>
 4         <meta charset="UTF-8">
 5         <title>Vue中的动画</title>        
 6         <style>
 7             .fade-enter,
 8             .fade-leave-to {
 9                 opacity: 0;
10             }
11             .fade-enter-active,
12             .fade-leave-active {
13                 transition: opacity 3s;
14             }
15             
16         </style>
17     </head>
18     <body>    
19         <div id="app">
20             <transition name="fade">
21                 <div v-if="show">hello world</div>
22             </transition>
23             <button @click="handleBtnClick">change</button>
24         </div>
25         
26         
27         <!-- 开发环境版本，包含了用帮助的命令行警告 -->
28         <script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
29         <script type="text/javascript">
30             
31             var app = new Vue({
32                 el: '#app',
33                 data:　{
34                     show: true
35                 },
36                 methods: {
37                     handleBtnClick: function() {
38                         this.show = !this.show;
39                     }
40                 }
41             })
42             
43         </script>
44     </body>
45 </html>

动画由transition标签包裹，class中的名字由transition的name属性来定，例如name = "fade",则class名为.fade-enter,如果没有name,则默认class名为v-, 例如.v-enter, .v-enter-active