js实现自定义进度条效果

  

   *{margin:0;padding:0;}

   html,body{height:100%;}

   ul{list-style:none;}

   .cf:after{content:"";display:block;clear:both;height: 0;}

   #bar{height:20px;margin:100px 10px; margin-left: 50px}

   #bar div{float:left;position:relative;}

   #bar .staged, #bar .progress{border-color:#4CA8FF;}

   #bar .staged i{position:relative;overflow:hidden;display:block;width:inherit;height:inherit;}

   #bar .staged i:before{content:"";display:block;width:0;height:inherit;border-radius:50%;}

   #bar .progress {width:120px;height:inherit;margin-left:-4px;z-index:1;border-style:solid;border-width:2px 0;}

   #bar .progress:nth-child(2) i{border-left-width:2px;border-top-left-radius:6px;border-bottom-left-radius:6px;}

   #bar .progress:nth-child(2){border-left-width:2px;border-top-left-radius:10px;border-bottom-left-radius:10px;}

   #bar .progress:last-child{border-right-width:2px;border-top-right-radius:10px;border-bottom-right-radius:10px;}

   #bar .progress i{width:0;height:inherit;display:block;border-radius:0 10px 10px 0;position:relative;font-style:normal;}

   #bar .progress, #bar .staged{background:#7d7d7d;}

   #bar .sp i:before, #bar .progress i{background:#4CA8FF;}

   #bar .staged:not(:first-child){margin-left:-4px; }

   #bar .staged:before{position:absolute;content:attr(data-text);width:inherit;height:inherit;top:90%;left:0;}

   #bar .staged:after{content:attr(data-value);color:#fff;width:inherit;height:inherit;position:absolute;top:0;left:0;}

   #bar .sp i:before{width:100%;transition:width 1s;}

   .msg:before, .msg:after{display:block;position:absolute;border-style:solid;border-color:#ccc;background:#fff;top:30px;}

   .msg:before{content:attr(data-text);width:200px;height:40px;line-height:40px;font-size:12px;text-align:center;border-radius:4px;border-width:1px;top:-68px;left:calc(100%  - 114px);}

   .msg:after{content:"";width:14px;height:14px;transform:rotate(45deg);border-width:0  1px 1px 0;top:-34px;left:calc(100% - 20px);}

   var progressBar = (function(){

    var $ = function(sele){

     return document.querySelectorAll(sele);

    }

    return function(a){

     var getValue = function(obj,attr){

      return Number(obj.getAttribute(a.value));

     }

     var box = $(a.box)[0];

     var value = getValue(box);

     var text = box.getAttribute(a.text);

     var staged = $(a.staged);

     var progress = $(a.progress);

     var i = 0, index = 0, num = 0, numV = 0, n = 1, af_index = 0, timeout = 0, stopAm = null;

     var af = function(fn){

      if(!requestAnimationFrame || !cancelAnimationFrame){

       clearTimeout(af_index);

       af_index = setTimeout(fn, 1000/60);

      }

      else{

       cancelAnimationFrame(af_index);

       af_index = requestAnimationFrame(fn);

      }

     }

     var setMsg = function(){

      var msg = progress[index];

      if(a.note){

        var arr = text.split(a.note);

        text = arr[0] + n + arr[1];

      }

      msg.setAttribute("data-text", text);

      msg.className = a.msg;

     }

     var animation = function(){

      if(i == 0){

       if(staged.length == index + 1){

        numV = value * 2;

       }

       else numV = getValue(staged[index + 1]);

       if(n == 0) {

        progress[index].style.width = "1%";

        return

       };

       if(n <0&& staged.length > index + 1){

        n = numV - value;

        if(Number(progress[index].style.width.split("%")[0])<5) progress[index].style.width="3%";

        setMsg();

        return;

       }

      }

      num=Math.ceil(++i * numV / 100);

      if(num > value){

       num = value;

       //console.log(num)

       n = numV - num;

       if(n > 0){

        if(staged.length > index + 1) setMsg();

        return;

       }

      }

      if(i == 100){

       staged[index + 1].className += " " + a.stagedProgress;

      }

      if(i > 105){ //105% 宽，自己根据样式调整。

       num = numV;

       index++;

       i = 0;

       timeout = setTimeout(function(){

        af(animation);

        clearTimeout(timeout);

       }, a.stagedSleep);

       return;

      }

      progress[index].style.width = i + "%";

      af(animation);

     }

     animation()

    }

   })();

   progressBar({

    box : "#bar",

    text : "data-text", // box 的属性

    note : "[number]", // box 的属性 （可以省略，计算好直接写入提示语句。）;

    msg : "msg",

    staged : ".staged",

    progress : ".progress i",

    stagedProgress : "sp",

    value : "data-value",

    stagedSleep : "900",

    sleep : "3000"

   });