IScroll5实现下拉刷新上拉加载的功能实例

Z时代
2024-01-10
分类：综合

声明：虽然本文章为原创，但是很大部分参考了博客园博主MRxia的一篇iscroll的下拉刷新的实现方式，我个人把demo简化了一下。

实现效果：类似网易新闻加载新闻列表（好吧，我的只能算是基础版，如要添加动图或者css样式或者canvas效果请自行脑补）

外部引入js文件，必须是iscroll-probe.js，这点是很重要的，因为基础版的 iscroll.js 插件并不支持实例化的IScroll对象的on事件绑定，当然还是要引入jQuery简化一下开发

以下是全局的css样式，当然你也可以直接复制过去，前面的是默认的iscroll的demo的样式，后面的pulldown-tips样式是作为绝对定位，当用户下拉不超过40px时显示“下拉刷新”的提示，下拉刷新后会被隐藏起来


<style type="text/css"> 
* { 
  -webkit-box-sizing: border-box; 
  -moz-box-sizing: border-box; 
  box-sizing: border-box; 
} 
html { 
  -ms-touch-action: none; 
} 
body,ul,li { 
  padding: 0; 
  margin: 0; 
  border: 0; 
} 
body { 
  font-size: 12px; 
  font-family: ubuntu, helvetica, arial; 
  overflow: hidden; /* this is important to prevent the whole page to bounce */ 
} 
#header { 
  position: absolute; 
  z-index: 2; 
  top: 0; 
  left: 0; 
  width: 100%; 
  height: 45px; 
  line-height: 45px; 
  background: #CD235C; 
  padding: 0; 
  color: #eee; 
  font-size: 20px; 
  text-align: center; 
  font-weight: bold; 
} 
#footer { 
  position: absolute; 
  z-index: 2; 
  bottom: 0; 
  left: 0; 
  width: 100%; 
  height: 48px; 
  background: #444; 
  padding: 0; 
  border-top: 1px solid #444; 
} 
#wrapper { 
  position: absolute; 
  z-index: 1; 
  top: 45px; 
  bottom: 48px; 
  left: 0; 
  width: 100%; 
  background: #ccc; 
  overflow: hidden; 
} 
#scroller { 
  position: absolute; 
  z-index: 1; 
  -webkit-tap-highlight-color: rgba(0,0,0,0); 
  width: 100%; 
  -webkit-transform: translateZ(0); 
  -moz-transform: translateZ(0); 
  -ms-transform: translateZ(0); 
  -o-transform: translateZ(0); 
  transform: translateZ(0); 
  -webkit-touch-callout: none; 
  -webkit-user-select: none; 
  -moz-user-select: none; 
  -ms-user-select: none; 
  user-select: none; 
  -webkit-text-size-adjust: none; 
  -moz-text-size-adjust: none; 
  -ms-text-size-adjust: none; 
  -o-text-size-adjust: none; 
  text-size-adjust: none; 
} 
#scroller ul { 
  list-style: none; 
  padding: 0; 
  margin: 0; 
  width: 100%; 
  text-align: left; 
} 
#scroller li { 
  padding: 0 10px; 
  height: 40px; 
  line-height: 40px; 
  border-bottom: 1px solid #ccc; 
  border-top: 1px solid #fff; 
  background-color: #fafafa; 
  font-size: 14px; 
} 
#pullDown,#pullUp,.pulldown-tips{ 
  height:40px; 
  line-height:40px; 
  text-align:center; 
} 
  .pulldown-tips{ 
    position:absolute; 
    top:-40px; 
    left:0; 
    width:100%; 
  } 
</style>

html结构在默认demo的基础上在scoller里面添加刷新/加载数据提示


<body onload="load()"> 
<div id="header">iScroll</div> 
<div id="wrapper"> 
  <div id="scroller"> 
  <div id="pullDown" class=""><div class="pullDownLabel"></div></div> 
    <div class="pulldown-tips">下拉刷新</div> 
    <ul id="list"> 
      <li>Pretty row 1</li> 
      <li>Pretty row 2</li> 
      <li>Pretty row 3</li> 
      <li>Pretty row 4</li> 
      <li>Pretty row 5</li> 
      <li>Pretty row 6</li> 
      <li>Pretty row 7</li> 
      <li>Pretty row 8</li> 
      <li>Pretty row 9</li> 
      <li>Pretty row 10</li> 
      <li>Pretty row 11</li> 
      <li>Pretty row 12</li> 
      <li>Pretty row 13</li> 
      <li>Pretty row 14</li> 
      <li>Pretty row 15</li> 
      <li>Pretty row 16</li> 
      <li>Pretty row 17</li> 
      <li>Pretty row 18</li> 
      <li>Pretty row 19</li> 
      <li>Pretty row 20</li> 
    </ul> 
    <div id="pullUp" class=""> 
    <div class="pullUpLabel">加载更多</div> 
    </div> 
  </div> 
</div> 
<div id="footer"></div> 
</body>

js需要说明的是，这里的scroll事件当然不是原生dom的scroll事件，而是IScroll对象的滚动事件，类似touchmove事件，scrollEnd事件也类似touchend事件，在滚动结束后执行


<script type="text/javascript"> 
  function load () { 
    var myScroll, 
          pullDown = $("#pullDown"), 
          pullUp = $("#pullUp"), 
          pullDownLabel = $(".pullDownLabel"), 
          pullUpLabel = $(".pullUpLabel"), 
          container = $('#list'), 
          loadingStep = 0;//加载状态0默认，1显示加载状态，2执行加载数据，只有当为0时才能再次加载，这是防止过快拉动刷新 
      pullDown.hide(); 
      pullUp.hide(); 
      myScroll = new IScroll("#wrapper", { 
        scrollbars: true, 
        mouseWheel: false, 
        interactiveScrollbars: true, 
        shrinkScrollbars: 'scale', 
        fadeScrollbars: true, 
        scrollY:true, 
        probeType: 2, 
        bindToWrapper:true 
      }); 
      myScroll.on("scroll",function(){ 
        if(loadingStep == 0 && !pullDown.attr("class").match('refresh|loading') && !pullUp.attr("class").match('refresh')){ 
          if(this.y > 40){//下拉刷新操作 
            $(".pulldown-tips").hide(); 
            pullDown.addClass("refresh").show(); 
            pullDownLabel.text("松手刷新数据"); 
            loadingStep = 1; 
            myScroll.refresh(); 
          }else if(this.y < (this.maxScrollY - 14)){//上拉加载更多 
            pullUp.addClass("refresh").show(); 
            pullUpLabel.text("正在载入"); 
            loadingStep = 1; 
            pullUpAction(); 
          } 
        } 
      }); 
      myScroll.on("scrollEnd",function(){ 
        if(loadingStep == 1){ 
          if( pullDown.attr("class").match("refresh") ){//下拉刷新操作 
            pullDown.removeClass("refresh").addClass("loading"); 
            pullDownLabel.text("正在刷新"); 
            loadingStep = 2; 
            pullDownAction(); 
          } 
        } 
      }); 
    function pullDownAction(){ 
      setTimeout(function(){ 
        var li, i; 
        for (i = 0,li = ""; i < 3; i++) { 
          li += "<li>" + "new Add " + new Date().toLocaleString() + " ！" + "</li>"; 
        } 
        container.prepend(li); 
        pullDown.attr('class','').hide(); 
        myScroll.refresh(); 
        loadingStep = 0; 
        $(".pulldown-tips").show(); 
      },1000); 
    } 
    function pullUpAction(){ 
      setTimeout(function(){ 
        var li, i; 
        for (i = 0,li = ""; i < 3; i++) { 
          li += "<li>" + "new Add " + new Date().toLocaleString() + " ！" + "</li>"; 
        } 
        container.append(li); 
        pullUp.attr('class','').hide(); 
        myScroll.refresh(); 
        loadingStep = 0; 
      },1000); 
    } 
    document.addEventListener('touchmove', function (e) { e.preventDefault(); }, false); 
    } 
</script>