先看思路流程
image.png
提示：
要理解下面的代码需要掌握几个知识点
下面代码的关键是 state这个枚举，通过改变它来实现各种状态的切换
scrollList.vue
<template>
<div class="index">
<my-scroll :page="page" :on-refresh="onRefresh" :on-pull="onPull">
<div slot="scrollList">
<ul>
<li v-for="(x,index) in list" :key="index">列表{{x}}--{{index}}</li>
</ul>
</div>
</my-scroll>
</div>
</template>
<script type="text/javascript">
import myScroll from '@/components/scroll/scroll.vue'
export default {
components:{
myScroll
},
data(){
return{
list:[],
page:{
counter:1,
total:3
},
}
},
mounted(){
for(let i=0;i<20;i++){
this.list.push(i)
}
},
methods:{
onRefresh(mun){ //下拉刷新的回调
setTimeout(()=>{ //模拟异步加载数据
this.list.unshift('更新的数据')
this.$root.$emit('setState',4)
},500)
},
onPull(mun){ //加载回调
if(this.page.counter<=this.page.total){
setTimeout(()=>{
this.page.counter++
for(let i=20;i<23;i++){
this.list.push(i)
}
this.$root.$emit('setState',6)
},1000)
}else{
this.$root.$emit('setState',7)
}
},
},
}
</script>
<style lang="less" scoped>
.index{
color: black;
height: 50%;
background-color: #bbbbbb;
overflow-y: scroll;
ul{margin: 0px;list-style: none;}
}
</style>
scroll.vue
<template>
<div class="my-scroll" ref="myScroll"
@touchstart="touchStart($event)"
@touchmove="touchMove($event)"
@touchend="touchEnd($event)">
<!-- 下拉提示语 -->
<div class="scroll-top" :style="{height:top+'px'}">
<div v-if="aspect=='down' ">
<p v-if="state==1">下拉刷新 </p>
<p v-if="state==2">松开刷新</p>
<p v-if="state==3"> <i><img :src="Load"/></i> <br/> 刷新中 </p>
<p v-if="state==4"> <i><img :src="Load"/></i> <br/> 刷新完成 </p>
</div>
</div>
<!--列表容器-->
<div class="scroll-list" :style="{ transform: 'translate3d(0, ' + top + 'px, 0)'}">
<slot name='scrollList'></slot>
<!--底部提示语-->
<div class="scroll-bottom">
<div v-if="state==5">加载中</div>
<div v-if="state==6">加载完成</div>
<div v-if="state==7">没有更多</div>
</div>
</div>
</div>
</template>
<script type="text/javascript">
import Load from '../../images/load.gif'
export default {
name: 'myScroll',
props: {
'page': {
type: Object, //counter:当前页 pageStart:开始页数 pageEnd:结束页数 total:总页数
require: true,
},
'onRefresh': { //刷新回调
type: Function,
require: true
},
'onPull': { //加载回调
type: Function,
require: true
}
},
data() {
return {
Load,
pageX: 0, /*滑动的开始坐标*/
pageY: 0, /*滑动的开始坐标*/
scrollPosition: 0,
myScroll: null,
myScrollList: null,
top: 0,
aspect: null, //1:向上 2:向下
listHeight: 0,
state: 0,
/*默认是0，表示默认开始的状态*/
}
},
mounted() {
this.myScroll = this.$refs.myScroll //获取滑条dom
this.myScrollList = this.myScroll.children[1] //获取列表dom
this.myScroll.addEventListener('scroll', (e) => { //监听滚动条事件
let listHeight = this.myScrollList.offsetHeight //列表总高度
let listScrollTop = e.target.scrollTop + this.myScroll.offsetHeight //当前滚动条位置
console.log(listHeight - listScrollTop)
if ( this.aspect ==null&& listHeight - listScrollTop < 10) {
this.aspect = 'up'//防止在底部多次触发
this.state = 5; //加载中
this.onPull(this.state)
}
})
},
created() {
this.$root.$on('setState', (index) => { //修改状态
this.state = index
if (index == 4) { //代表下拉结束
setTimeout(() => {
this.state = 0
this.top = 0
}, 300)
}
if(index ==6){ //代表上拉结束
this.state = 6;
this.aspect=null;
}
if(index==7){
this.state = 7;
this.aspect=null;
}
})
},
methods: {
touchStart(e) { //触摸事件
this.pageX = e.targetTouches[0].pageX
this.pageY = e.targetTouches[0].pageY
},
touchMove(e) { //触摸滑动事件
e.preventDefault()
this.scrollPosition = this.myScroll.scrollTop //获取滚动条位置
if (e.targetTouches[0].pageY > this.pageY) {
this.aspect = 'down'//向下滑动
if (this.myScroll.scrollTop == 0) {
let diff = e.targetTouches[0].pageY - this.pageY - this.scrollPosition;
this.top = Math.pow(diff, 0.9)
console.log(diff)
if (diff > 100) {
this.state = 2 //松开刷新 够距离
} else{
this.state = 1 //下拉刷新 不够距离
}
}
}
},
touchEnd(e) {
if (this.aspect == 'down' && this.state == 2) { //下拉够距离-处理
this.top = 100
this.state = 3//刷新中
this.onRefresh(this.state)
} else {
this.state = 0
this.top = 0
}
},
},
}
</script>
<style lang="less" scoped>
.my-scroll {
color: black;
max-width: 100%;
max-height: 100%;
height: 100%;
overflow: hidden;
overflow-y: scroll;
-webkit-overflow-scrolling: touch;
will-change: transform;
transition: all 450ms;
backface-visibility: hidden;
perspective: 1000;
position: relative;
.scroll-top {
text-align: center;
display: flex;
position: absolute;
top: 0;
left: 0;
width: 100%;
div {
display: flex;
height: auto;
width: 100%;
justify-content: center;
align-items: center;
flex-wrap: wrap;
i {
flex: 1 0 100%;
display: block;
height: 0.4rem;
}
img {
width: 0.8rem;
}
p {
flex: 1 0 100%;
}
}
}
.scroll-list {
overflow: hidden;
}
.scroll-bottom {
text-align: center;
line-height: 40px;
}
}
</style>
