vue3学习（十一）transition动画组件

Vue 提供了 transition 的封装组件，可以给元素和组件添加进入/离开过渡动画：一下情景可以使用

• 条件渲染 (使用 v-if)
• 条件展示 (使用 v-show)
• 动态组件
• 组件根节点

对transition组件的name属性自定义，并在css中写入对应的样式

<button @click="flag = !flag">显示或隐藏</button>
<transition name="box">
   <div class="box" v-if="flag"></div>
</transition>

.box{
    width: 100px;
    height: 100px;
    background-color: blue;
}
// 进入的过渡动画
// 开始进入
.box-enter-from{
    height: 0;
    width: 0;
}
// 进入过程
.box-enter-active{
    transition: all 2s ease;
}
// 进入结束
.box-enter-to{
    height: 100px;
    width: 100px;
}
// 离开的过渡动画
// 开始离开
.box-leave-from{
    height: 100px;
    width: 100px;
    transform: rotate(360deg);
}
// 离开过程
.box-leave-active{
    transition: all 2s ease;
}
// 离开结束
.box-leave-to{
    height: 0;
    width: 0;
}

2. 自定义过渡 class 类名

• enter-from-class
• enter-active-class
• enter-to-class
• leave-from-class
• leave-active-class
• leave-to-class

<button @click="flag = !flag">显示或隐藏</button>
<transition 
    enter-from-class="e-from" 
    enter-active-class="e-active" 
    enter-to-class="e-to" 
name="fade">
   <div class="box" v-if="flag"></div>
</transition>


// 对应的css
.e-from{
    height: 0;
    width: 0;
}
.e-active{
    transition: all 2s ease;
}
.e-to{
    height: 100px;
    width: 100px;
}

通过自定义class可以 结合css动画库animate css使用

安装库 npm install animate.css -s

在组件中引入 import 'animate.css'

文档 Animate.css | A cross-browser library of CSS animations.

3.transition 8个生命周期

        <transition 
            @before-enter="EnterFrom"
            @enter="EnterActive"
            @after-enter="EnterTo"
            @enter-cancelled="EnterCancel"
            @before-leave="LeaveFrom"
            @leave="LeaveActive"
            @after-leave="LeaveTo"
            @leave-cancelled="LeaveCancel"
        name="fade">
            <div class="shop" v-if="flag"></div>
        </transition>

const EnterFrom = (el:Element)=>{
    console.log('进入之前');
}
const EnterActive = (el:Element, done:Function)=>{
    console.log('进入的过渡曲线');
    setTimeout(()=>{
        done()
    },3000)
}
const EnterTo = (el:Element)=>{
    console.log('过渡完成');  
}
const EnterCancel = (el:Element)=>{
    console.log('执行过渡效果被打断');
}
const LeaveFrom = ()=>{
    console.log('离开之前');
    
}
const LeaveActive = (el:Element, done:Function)=>{
    console.log('离开的过渡曲线');
    setTimeout(()=>{
        done()
    },3000)
}
const LeaveTo = (el:Element)=>{
    console.log('离开过渡完成');  
}
const LeaveCancel = (el:Element)=>{
    console.log('离开过渡效果被打断');
}

4. appear

通过这个属性可以设置初始节点的过渡动画，对应三个状态

<transition 
    appear
    appear-active-class=""
    appear-from-class=""
    appear-to-class=""
name="fade">
  <div class="shop" v-if="flag"></div>
</transition>

页可以结合css动画库animate css使用