vue.js移动端app之上拉加载以及下拉刷新实战

import BScroll from 'better-scroll'

//是否开启下拉刷新，可传入true或者false,如果需要更多配置可以传入一个对象

pullDownRefresh：{
  threshold:80,
  stop:40
}

//是否开启上拉加载，同上，上拉无stop参数，这里需要注意是负数
pullUpLoad：{
  threshold:-80,
}

/**
 * 
 * @param threshold 触发事件的阀值，即滑动多少距离触发
 * @param stop 下拉刷新后回滚距离顶部的距离（为了给loading留出一点空间）
 */

//在util.js里面加一个方法
export function getDeviceRatio(){
  var isAndroid = window.navigator.appVersion.match(/android/gi);
  var isIPhone = window.navigator.appVersion.match(/iphone/gi);
  var devicePixelRatio = window.devicePixelRatio;
  var dpr;
  if (isIPhone) {
    // iOS下，对于2和3的屏，用2倍的方案，其余的用1倍方案
    if (devicePixelRatio >= 3) {        
      dpr = 3;
    } else if (devicePixelRatio >= 2){
      dpr = 2;
    } else {
      dpr = 1;
    }
  } else {
    // 其他设备下，仍旧使用1倍的方案
    dpr = 1;
  }
  return dpr
}

import{ DEVICE_RATIO} from '../base/js/api.js'
/*获取当前缩放比*/
const DEVICE_RATIO=getDeviceRatio();


 /*下拉配置*/
const DOWN_CONFIG={
 threshold:80*DEVICE_RATIO,
 stop:40*DEVICE_RATIO
}
/*上拉配置*/
const UP_CONFIG={
 threshold:-80*DEVICE_RATIO,
}

this.scroller = new BScroll(scrollWrap,{
 click:true,
 probeType:3,
 pullDownRefresh:DOWN_CONFIG,
 pullUpLoad:UP_CONFIG
});

/*下拉事件*/
this.scroller.on('pullingDown',()=> {});

/*上拉事件*/
this.scroller.on('pullingUp',()=>{});

this.scroller.on('pullingDown',()=> {
  
  <!-- 1. 发送请求获取数据 -->
  
  <!-- 2. 获取成功后，通知事件完成 -->
  
  <!-- 3. 修改data数据，在nextTick调用refresh -->
});

watch:{
 dataList(){
  this.$nextTick(()=>{
   this.scroller.refresh(); 
  }) 
 }
},

this.scroller.on("scroll",(pos)=>{ 
  //获取整个滚动列表的高度
  var height=getStyle(scroller,"height");

  //获取滚动外层wrap的高度
  var pageHeight=getStyle(scrollWrap,"height");

  //触发事件需要的阀值
  var distance=80*DEVICE_RATIO;

  //参数pos为当前位置

  if(pos.y>distance){ 

    //console.log("下拉");
    //do something
   
  }else if(pos.y-pageHeight<-height-distance){

    //console.log("上拉");
    //do something
  }

var onPullUp=true;

var onPullDown=true;

 <template>
  <div ref="wrapper" class="list-wrapper"> 
    <div class="scroll-content">    
      <slot></slot>     
    </div>   
  </div>
</template>

 export default {
  props: {
   dataList:{
    type: Array,
    default: []
   },
   probeType: {
    type: Number,
    default: 3
   },
   click: {
    type: Boolean,
    default: true
   },  
   pullDownRefresh: {
    type: null,
    default: false
   },
   pullUpLoad: {
    type: null,
    default: false
   },  
  }

mounted() {
  this.scroll = new BScroll(this.$refs.wrapper, {
      probeType: this.probeType,
      click: this.click,    
      pullDownRefresh: this.pullDownRefresh,
      pullUpLoad: this.pullUpLoad,
    })

  this.scroll.on('pullingUp',()=> {
    if(this.continuePullUp){
      this.beforePullUp();
      this.$emit("onPullUp","当前状态：上拉加载");
    }
  });

  this.scroll.on('pullingDown',()=> {
    this.beforePullDown();
    this.$emit("onPullDown","当前状态：下拉加载更多");
  }); 
}

  <Scroller 
    id="scroll"
    ref="scroll" 
    :dataList="filmList"
    :pullDownRefresh="DOWN_CONFIG"
    :pullUpLoad="UP_CONFIG"
    @onPullUp="pullUpHandle"
    @onPullDown="pullDownHandle"
   >

    <ul>
       <router-link class="film-list" v-for="(v,i) in filmList" :key="v.id" tag="li" :to='{path:"/film-detail/"+v.id}'>
          <div class="film-list__img">
             <img v-lazy="v.images.small" alt="" />        
          </div>
          <div class="film-list__detail">
            <p class="film-list__detail__title">{{v.title}}</p>
            <p class="film-list__detail__director">导演：{{filterDirectors(v.directors)}}</p>
            <p class="film-list__detail__year">年份：{{v.year}}<span>{{v.stock}}</span></p>
            <p class="film-list__detail__type">类别：{{v.genres.join(" / ")}}<span></span></p>
            <p class="film-list__detail__rank">评分：<span>{{v.rating.average}}分</span></p>
          </div>             
        </router-link>
     </ul>     
   </Scroller>

 computed:{
    scrollElement(){
      return this.$refs.scroll
    }
  }

   <template>
     <div ref="wrapper" class="list-wrapper"> 
       <div class="scroll-content">    
         <slot></slot>
         <div>
           <PullingWord v-show="!inPullUp&&dataList.length>0" :loadingWord="beforePullUpWord"></PullingWord>
           <Loading v-show="inPullUp" :loadingWord='PullingUpWord'></Loading>
         </div>    
       </div> 

       <transition name="pullDown">
         <Loading class="pullDown" v-show="inPullDown" :loadingWord='PullingDownWord'></Loading>
       </transition> 
     </div>
   </template>


   <script >
    import BScroll from 'better-scroll'
    import Loading from './loading.vue'
    import PullingWord from './pulling-word'

    const PullingUpWord="正在拼命加载中...";
    const beforePullUpWord="上拉加载更多";
    const finishPullUpWord="加载完成";

    const PullingDownWord="加载中...";

    export default {
     props: {
      dataList:{
       type: Array,
       default: []
      },
      probeType: {
       type: Number,
       default: 3
      },
      click: {
       type: Boolean,
       default: true
      },  
      pullDownRefresh: {
       type: null,
       default: false
      },
      pullUpLoad: {
       type: null,
       default: false
      },  
     },
     data() {
       return { 
         scroll:null,
         inPullUp:false,
         inPullDown:false,
         beforePullUpWord,
         PullingUpWord,
         PullingDownWord,
         continuePullUp:true
       }
     },
      
     mounted() {
       setTimeout(()=>{
         this.initScroll();

         this.scroll.on('pullingUp',()=> {
           if(this.continuePullUp){
             this.beforePullUp();
             this.$emit("onPullUp","当前状态：上拉加载");
           }
         });

         this.scroll.on('pullingDown',()=> {
           this.beforePullDown();
           this.$emit("onPullDown","当前状态：下拉加载更多");
         });

       },20)
       
     },
     methods: {
       initScroll() {
         if (!this.$refs.wrapper) {
           return
         }
         this.scroll = new BScroll(this.$refs.wrapper, {
           probeType: this.probeType,
           click: this.click,    
           pullDownRefresh: this.pullDownRefresh,
           pullUpLoad: this.pullUpLoad,
         })
       },
       beforePullUp(){
         this.PullingUpWord=PullingUpWord;
         this.inPullUp=true;
       }, 
       beforePullDown(){
         this.disable();
         this.inPullDown=true;
       },
       finish(type){
         this["finish"+type]();
         this.enable();
         this["in"+type]=false; 
       },
       disable() {
         this.scroll && this.scroll.disable()
       },
       enable() {
         this.scroll && this.scroll.enable()
       },
       refresh() {
         this.scroll && this.scroll.refresh()
       }, 
       finishPullDown(){
         this.scroll&&this.scroll.finishPullDown()
       },
       finishPullUp(){
         this.scroll&&this.scroll.finishPullUp()
       },   
     },
        
     watch: {
       dataList() {        
         this.$nextTick(()=>{
           this.refresh();            
         }) 
       }
     },
     components: {
       Loading,
       PullingWord
     }
    }

   </script>