什么是 better-scroll
better-scroll 是一个移动端滚动的解决方案，它是基于 iscroll 的重写，它和 iscroll 的主要区别在这里 。better-scroll 也很强大，不仅可以做普通的滚动列表，还可以做轮播图、picker 等等。
<template> <div> <div> <div ref="menuWrapper"> </div> <div ref="foodWrapper"> </div> </div> </div> </template>
与1.0版本不同的是,我们使用的是ref
<script type="text/ecmascript-6"> import BScroll from "better-scroll"; export default { data(){ return { currentIndex:1, goods:[] } }, created(){ this.classMap=['decrease','discount','special','invoice','guarantee']; this.$http.get('/api/goods').then((response)=>{ response=response.body; if (response.errno===ERR_OK) { this.goods=response.data; } //dom结构加载结束(nextTick这个接口是计算dom相关的,要确保原生dom已经渲染了) this.$nextTick(()=>{ this._initScroll(); }); }); }, methods:{ _initScroll(){ // 使用better-scroll实现的关键代码 this.menuScroll=new BScroll(this.$refs.menuWrapper,{click:true}); this.foodScroll=new BScroll(this.$refs.foodWrapper,{click:true}); } } }; </script>
很简单这样页面就可以滚动了,如下图
但是,这样左右两个页面并没有联动起来,需要我们再定义一个方法来计算滚动的高度,以及在计算属性中计算左侧当前索引在哪里
从而定义左侧边栏的位置
computed:{ //用来计算左侧当前索引在哪，从而定位到左侧边栏的位置 currentIndex(){ for (let i = 0; i < this.listHeight.length; i++) { var height1=this.listHeight[i] ; var height2=this.listHeight[i+1]; if(!height2||(this.scrollY >= height1 && this.scrollY < height2)){ return i; } } return 0; } }, methods:{ _initScroll(){ // 使用better-scroll实现的关键代码 this.menuScroll=new BScroll(this.$refs.menuWrapper,{click:true}); this.foodScroll=new BScroll(this.$refs.foodWrapper,{ click: true, //探针作用，实时监测滚动位置 probeType: 3 }); this.foodScroll.on('scroll',(pos)=>{ this.scrollY=Math.abs(Math.round(pos.y)) }); }, _calculateHeight(){ let foodList=this.$refs.foodWrapper.getElementsByClassName('food-list-hook'); let height=0; this.listHeight.push(height); for (var i = 0; i < foodList.length; i++) { let item=foodList[i]; height+=item.clientHeight; this.listHeight.push(height); } } } //dom结构加载结束(nextTick这个接口是计算dom相关的,要确保原生dom已经渲染了) this.$nextTick(()=>{ this._initScroll(); this._calculateHeight(); });
在dom渲染后,也是需要计算高度的.
滑动右边,实现左边联动已经实现了,接下来就是,点击左边的菜单,右边的食物相应滚动到具体的位置
给左边菜单绑定一个事件:@click="selectMenu(index,$event)"
/左边的菜单项的点击事件 selectMenu(index,event){ //自己默认派发事件时(BScroll),_constructed默认为true.但原生的浏览器并没有这个属性 if (!event._constructed) { return; } //运用BScroll滚动到相应位置 //运用index去找到对应的右侧位置 let foodList=this.$refs.foodWrapper.getElementsByClassName('food-list-hook'); //滚动到相应的位置 let el=foodList[index]; //设置滚动时间 this.foodScroll.scrollToElement(el,2000); }
至此,整个联动实现的,完整代码如下
<template> <div> <div> <div ref="menuWrapper"> <ul> <li v-for="(item,index) in goods" :class="{'current':currentIndex===index}" @click="selectMenu(index,$event)"> <span> <span v-show="item.type>0" :class="classMap[item.type]"></span>{{item.name}} </span> </li> </ul> </div> <div ref="foodWrapper"> <ul> <li v-for="(item,index) in goods"> <h1>{{item.name}}</h1> <ul> <li v-for="food in item.foods"> <div> <img :src="food.icon" alt=""> </div> <div> <h2>{{food.name}}</h2> <p>{{food.description}}</p> <div> <span>月售{{food.sellCount}}份</span> <span>好评率{{food.rating}}%</span> </div> <div> <span>¥{{food.price}}</span><span v-show="food.oldPrice">¥{{food.oldPrice}}</span> </div> </div> </li> </ul> </li> </ul> </div> </div> </div> </template> <script type="text/ecmascript-6"> import BScroll from "better-scroll"; const ERR_OK=0; export default { props:{ seller:{ type:Object } }, data(){ return { goods:[], listHeight:[], scrollY:0 } }, created(){ this.classMap=['decrease','discount','special','invoice','guarantee']; this.$http.get('/api/goods').then((response)=>{ response=response.body; if (response.errno===ERR_OK) { this.goods=response.data; } //dom结构加载结束(nextTick这个接口是计算dom相关的,要确保原生dom已经渲染了) this.$nextTick(()=>{ this._initScroll(); this._calculateHeight(); }); }); }, computed:{ //用来计算左侧当前索引在哪，从而定位到左侧边栏的位置 currentIndex(){ for (let i = 0; i < this.listHeight.length; i++) { var height1=this.listHeight[i] ; var height2=this.listHeight[i+1]; if(!height2||(this.scrollY >= height1 && this.scrollY < height2)){ return i; } } return 0; } }, methods:{ _initScroll(){ // 使用better-scroll实现的关键代码 this.menuScroll=new BScroll(this.$refs.menuWrapper,{click:true}); this.foodScroll=new BScroll(this.$refs.foodWrapper,{ click: true, //探针作用，实时监测滚动位置 probeType: 3 }); this.foodScroll.on('scroll',(pos)=>{ this.scrollY=Math.abs(Math.round(pos.y)) }); }, _calculateHeight(){ let foodList=this.$refs.foodWrapper.getElementsByClassName('food-list-hook'); let height=0; this.listHeight.push(height); for (var i = 0; i < foodList.length; i++) { let item=foodList[i]; height+=item.clientHeight; this.listHeight.push(height); } }, //左边的菜单项的点击事件 selectMenu(index,event){ //自己默认派发事件时(BScroll),_constructed默认为true.但原生的浏览器并没有这个属性 if (!event._constructed) { return; } //运用BScroll滚动到相应位置 //运用index去找到对应的右侧位置 let foodList=this.$refs.foodWrapper.getElementsByClassName('food-list-hook'); //滚动到相应的位置 let el=foodList[index]; //设置滚动时间 this.foodScroll.scrollToElement(el,2000); } } }; </script> <style lang="stylus"> @import "../../common/stylus/mixin.styl"; .goods display:flex position:absolute top:174px bottom:46px width:100% overflow:hidden .menu-wrapper flex:0 0 80px width: 80px background:#f3f5f7 .menu-item display:table height:54px width:56px padding:0 12px line-height:14px &.current position:relative z-index:10 margin-top:-1px background:#fff font-weight:700 .text border-none() .icon display:inline-block vertical-align:top margin-right:2px width:12px height:12px background-size:12px 12px background-repeat:no-repeat &.decrease bg-image('decrease_3') &.discount bg-image('discount_3') &.guarantee bg-image('guarantee_3') &.invoice bg-image('invoice_3') &.special bg-image('special_3') .text display:table-cell vertical-align:middle width:56px border-1px(rgba(7,17,27,0.1)) font-size:12px .food-wrapper flex:1 .title padding-left:14px font-size:12px color:rgb(147,153,159) height:26px border-left:2px solid #d9dde1 line-height:26px background:#f3f5f7 .food-item display:flex margin:18px padding-bottom:18px border-1px(rgba(7,17,27,0.1)) &:last-child border-none() margin-bottom:0 .icon flex:0 0 57px margin-right:10px .content flex:1 .name margin:2px 0 8px 0 height:14px line-height:14px font-size:14px color:rgb(7,17,27) .desc,.extra line-height:10px font-size:10px color:rgb(147,153,159) .desc margin-bottom:8px line-height:12px .extra .count margin-right:12px .price font-weight:700 line-height:24px .now margin-right:8px font-size:14px color:rgb(240,20,20) .old text-decoration:line-through font-size:10px color:rgb(147,153,159) </style>
总结