vue滚动轴插件better-scroll使用详解

跟做慕课网的vue高仿外卖项目中用到了一个很好用的插件BScroll，用来计算左侧menu栏对应右侧foods栏相应显示的食物区，如果不用插件就比较费事了，因此这里分享一下这个插件的简单使用：

一、项目中下载，并引入

在配置文件package.json中引入版本

"dependencies": {  "better-scroll": "^0.1.7" }

然后进入项目目录,打开cmd更新配置

npm i (i是install缩写)

最后引入，比如我在项目goods组件中使用则：

import BScroll from 'better-scroll';

二、举个栗子

需求是处于当前比如热销榜栏目，则菜单栏高亮。滚动到下一栏高亮栏目则下一栏菜单高亮。点击菜单中某一栏菜单该栏目高亮并且跳转到对应食物区。

下面是foods组件中的代码

template：

<template> <div class="goods">  <div class="menu-wrap" ref="menuWrap">//菜单栏   <ul>    <li v-for="(item,index) in goods" class="menu-item" :class="{'current':currentIndex===index}" @click="selectMenu(index,$event)">     <span class="text border-1px">      <span v-show="item.type>0" class="icon" :class="classMap[item.type]"></span>{{item.name}}     </span>    </li>   </ul>  </div>  <div class="foods-wrap" ref="foodsWrap">//食物栏  </div> </div></template>

script

<script type="text/ecmascript-6"> import Vue from 'vue'; import BScroll from 'better-scroll'; import shopcart from '@/components/shopcart/shopcart'; export default {  props: {//接收父组件传的数据   seller: {    type: Object   }  },  data () {   return {    goods: [],    listHeight: [],//菜单中一个菜单栏目的高度    scrollY: 0//定义的Y滚动轴及初始值   };  },  computed: {//计算属性   currentIndex () {//当前菜单栏在整个菜单中的下标index    for (let i = 0; i < this.listHeight.length; i++) {//遍历菜单中每个栏目的高度     let height1 = this.listHeight[i];//第i个栏目的高度     let height2 = this.listHeight[i + 1];//第i+1个栏目的高度     if (!height2 || (this.scrollY >= height1 && this.scrollY < height2)) {//根据当前滚动轴的位置得出index(如果第二个栏目不存在即第一个栏目是最后一个)或者(当前栏目高度大于等于第一个并且当前滚动轴小于第二个栏目高度)      return i;//如果满足则返回index     }    }    return 0;//初始值0   }  },  created () {   Vue.prototype.$http.get('/api/goods')    .then(res => {     this.goods = res.data.data;     this.$nextTick(() => {//      this._initScroll();      this._calculateHeight();     });    });   this.classMap = ['decrease', 'discount', 'special', 'invoice', 'guarantee'];  },  methods: {   selectMenu (index, event) {    if (!event._constructed) {     return;    }    let foodList = this.$refs.foodsWrap.getElementsByClassName('food-list-hook');    let el = foodList[index];    this.foodsScroll.scrollToElement(el, 300);   },   _initScroll () {    this.menuScroll = new BScroll(this.$refs.menuWrap, {     click: true    });    this.foodsScroll = new BScroll(this.$refs.foodsWrap, {probeType: 3    });    this.foodsScroll.on('scroll', (pos) => {     this.scrollY = Math.abs(Math.round(pos.y));     console.log(this.scrollY);    });   },   _calculateHeight () {    let foodList = this.$refs.foodsWrap.getElementsByClassName('food-list-hook');    let height = 0;    this.listHeight.push(height);    for (let i = 0; i < foodList.length; i++) {     let item = foodList[i];     height += item.clientHeight;     this.listHeight.push(height);    }   }  } };</script>