<style>
@keyframes fadeIn {
from {
opacity: 0;
}
to {
opacity: 1;
}
}
.fadeIn {
animation-name: fadeIn;
}
@keyframes fadeOut {
from {
opacity: 1;
}
to {
opacity: 0;
}
}
.fadeOut {
animation-name: fadeOut;
}
</style>
「完整事例地址：https://codesandbox.io/s/j4qnjvmwz9?from-embed 」
现在，我们可以控制实际的可见过渡时间，这使我们可重用的过渡变得灵活且易于使用。但是，如何过渡多个元素(如列表项)呢?
Transition group 支持
你想到的最直接的方法可能是创建一个新组件，比如fade-transition-group，然后将当前transition标签替换为transition-group标签，以实现 group transition。如果我们可以在相同的组件中这样做，并公开一个将切换到transition-group实现的group prop，那会怎么样呢?幸运的是，我们可以通过render函数或component和is属性来实现这一点。
// FadeTransition.vue <template>
<component :is="type"
:tag="tag"
enter-active-class="fadeIn"
leave-active-class="fadeOut"
move-class="fade-move"
v-bind="$attrs"
v-on="hooks">
<slot></slot>
</component>
</template>
<script>
export default {
props: {
duration: {
type: Number,
default: 300
},
group: {
type: Boolean,
default: false
},
tag: {
type: String,
default: "div"
}
},
computed: {
type() {
return this.group ? "transition-group" : "transition";
},
hooks() {
return {
beforeEnter: this.setDuration,
afterEnter: this.cleanUpDuration,
beforeLeave: this.setDuration,
afterLeave: this.cleanUpDuration,
leave: this.setAbsolutePosition,
...this.$listeners
};
}
},
methods: {
setDuration(el) {
el.style.animationDuration = `${this.duration}ms`;
},
cleanUpDuration(el) {
el.style.animationDuration = "";
},
setAbsolutePosition(el) {
if (this.group) {
el.style.position = "absolute";
}
}
}
};
</script>
<style>
@keyframes fadeIn {
from {
opacity: 0;
}
to {
opacity: 1;
}
}
.fadeIn {
animation-name: fadeIn;
}
@keyframes fadeOut {
from {
opacity: 1;
}
to {
opacity: 0;
}
}
.fadeOut {
animation-name: fadeOut;
}
.fade-move {
transition: transform 0.3s ease-out;
}
</style>
// App.vue
...
<div class="box-wrapper">
<fade-transition group :duration="300">
