学习内容:vue3实现轮播图组件封装
一:结构
<template>
<div class="x-carousel" @mouseenter="stop()" @mouseleave="start()">
<ul class="carousel-body">
<li
class="carousel-item"
v-for="(item, i) in sliders"
:key="i"
:class="{ fade: index === i }"
>
<RouterLink to="/">
<img :src="item.imgUrl" alt="" />
</RouterLink>
</li>
</ul>
<a @click="toggle(-1)" href="javascript:;" class="carousel-btn prev"
><i class="iconfont icon-angle-left"></i
></a>
<a @click="toggle(1)" href="javascript:;" class="carousel-btn next"
><i class="iconfont icon-angle-right"></i
></a>
<div class="carousel-indicator">
<span
@click="index=i"
v-for="(item, i) in sliders"
:key="i"
:class="{ active: index === i }"
></span>
</div>
</div>
</template>
二: 样式
.x-carousel {
width: 100%;
height: 100%;
min-width: 300px;
min-height: 150px;
position: relative;
.carousel {
&-body {
width: 100%;
height: 100%;
}
&-item {
width: 100%;
height: 100%;
position: absolute;
left: 0;
top: 0;
opacity: 0;
transition: opacity 0.5s linear;
&.fade {
opacity: 1;
z-index: 1;
}
img {
width: 100%;
height: 100%;
}
}
&-indicator {
position: absolute;
left: 0;
bottom: 20px;
z-index: 2;
width: 100%;
text-align: center;
span {
display: inline-block;
width: 12px;
height: 12px;
background: rgba(0, 0, 0, 0.2);
border-radius: 50%;
cursor: pointer;
~ span {
margin-left: 12px;
}
&.active {
background: #fff;
}
}
}
&-btn {
width: 44px;
height: 44px;
background: rgba(0, 0, 0, 0.2);
color: #fff;
border-radius: 50%;
position: absolute;
top: 228px;
z-index: 2;
text-align: center;
line-height: 44px;
opacity: 0;
transition: all 0.5s;
&.prev {
left: 20px;
}
&.next {
right: 20px;
}
}
}
&:hover {
.carousel-btn {
opacity: 1;
}
}
}
</style>
三: 逻辑
如果页面中有多处使用轮播图,可以将其封装成一个全局组件,通过props控制该轮播图组件的图片数据,是否自动播放,间隔时长。
props:
// 轮播图数据
sliders: {
type: Array,
default: () => [],
},
// 是否自动轮播
autoPlay: {
type: Boolean,
default: false,
},
// 间隔时长
duration: {
type: Number,
default: 3000,
},
},
自动轮播的逻辑
const index = ref(0);
var timer = null;
const auroPlayFn = () => {
clearInterval(timer);
timer = setInterval(() => {
index.value++;
if (index.value >= props.sliders.length) {
index.value = 0;
}
}, props.duration);
};
通过watch监听数据改变后是否自动播放
watch(
() => props.sliders,
(newVal) => {
if (newVal.length && props.autoPlay) {
auroPlayFn();
}
},
{ immediate: true }
);
鼠标进入暂停定时器,离开开启定时器,给父元素绑定 @mouseenter="stop()" @mouseleave="start()"事件
const stop = () => {
if (timer) clearInterval(timer);
};
const start = () => {
if (props.sliders.length && props.autoPlay) {
auroPlayFn();
}
};
点击切换上/下一张
const toggle = (step) => {
const newIndex = index.value + step;
if (newIndex > props.sliders.length - 1) {
index.value = 0;
return;
}
if (newIndex < 0) {
index.value = props.sliders.length - 1;
return;
}
index.value = newIndex;
};
组件卸载时,清除定时器
onUnmounted(() => {
clearInterval(timer);
});
心得:
掌握了将轮播图组件封装成全局组件,当页面多个地方需要时,可以用一个组件实现,通过组件间通信实现不同轮播图之间数据的渲染