.wapper{scrollbar-3dlight-color:#000; position:relative; height:302px;width:300px;overflow:hidden;margin:0 auto;line-height:40px;text-align:center;}
 .area{background-color:#E2E2EF;width:100%; position:absolute;top:0px;left:0px;}
 .bar{position:absolute;top:0px;right:0px; height:100%;width:1rem;background-color:#ccc;}
 .scroll,.middle,.forward,.backward{display:block;cursor:pointer;position:absolute;right:0px;width:100%;}
 .forward,.backward{height:16px;background-color:#6868B1;}
 .middle{background-color:rgba(255, 255, 255, 0.22);top:16px;cursor:auto;}
 .scroll{position:absolute;top:0px;background-color:#C2C2E9;}
 .forward{top:0px;}
 .backward{bottom:0px;}

<div class="wapper">
 <div class="area">
  <p>1、this is content</p>
  <p>2、this is content</p>
  <p>3、this is content</p>
  <p>4、this is content</p>
  <p>5、this is content</p>
  <p>6、this is content</p>
  <p>7、this is content</p>
  <p>8、this is content</p>
  <p>9、this is content</p>
  <p>10、this is content</p>
  <p>11、this is content</p>
 </div>
 <div class="bar">
  <span class="forward"></span>
  <span class="middle"><em class="scroll"></em></span>
  <span class="backward"></span>
 </div>
</div>

<script type="text/javascript" src="../../lib/seajs/sea.js"></script>
<script type="text/javascript" src="../../lib/base/1.0.x/base.js"></script>
<script type="text/javascript">
seajs.use(['lib/jquery/1.11.x/index.js', '_example/simulationScroll/simulationScroll.js'], function($, scroll) {
 scroll.init({
  wapper: $('.wapper'), 
  distance: 10,
 });
});

define(function(require, exports, module) {

 'use strict';

 var $ = require('lib/jquery/1.11.x/index.js');

 var parameter = null;

 //检测设备类型
 var startWhen, endWhen, moveWhen;
 var u = navigator.userAgent; 

 if ( u.match(/\b(Windows\sNT|Macintosh)\b/) ) {
  // 鼠标
  startWhen = 'mousedown';
  endWhen = 'mouseup';
  moveWhen = 'mousemove';
 } else {
  // 触摸屏
  startWhen = 'touchstart';
  endWhen = 'touchend';
  moveWhen = 'touchmove';
 }

 var simulation = {

  _mousedownTimer: 0,
  _setintervalId: 0,
  _longClick: false, //是否长点击
  _turnOf: null, //滚动方向

  init: function(options) {

   var t = this;

   t._scroll = $('.scroll'); //滚动条

   t._wapper = options.wapper.find('.area'); //内容区域
   t._distance = options.distance; //点击上下按钮页面每次滚动的距离

   var forward = $('.forward'),
    middle = $('.middle'),
    backward = $('.backward');

   parameter = {
    view: t._wapper.parent().innerHeight(), //视图高度
    page: t._wapper.height(), //内容高度
    barArea: 0, //滚动条可移动范围
    scrollHeight: 0, //滚动条的高度
    scrollDistance: 0 //滚动条每次滚动的距离
   };

   //初始化滚动条
   if (parameter.page > parameter.view) {

    //滚动条可移动范围
    middle.height( parameter.view - forward.height() * 2);

    parameter.barArea = middle.height();

    //滚动条高度 = 滚动条可滚动范围 / （页面高度 / 可视高度）的百分比
    parameter.scrollHeight = parameter.barArea / (parameter.page / parameter.view) ;
    t._scroll.height(parameter.scrollHeight);

    //滚动条每次滚动的距离 = 滚动条可移动范围 * 页面每次滚动的百分比
    parameter.scrollDistance = parameter.barArea / (parameter.page / t._distance) ;

    //拖动滚动条
    t.liveEvent();

    //点击向前按钮,如果按下鼠标到松开鼠标的时长<100ms,则为单次点击
    forward.bind(startWhen, function(e){

     t._turnOf = 'forward';

     t.longPress(e, t.direction );

    }).bind(endWhen, function(e) { 

     t.mouseupFun(e, t.direction);

     t._turnOf = null;

    });

    //点击向后按钮
    backward.bind(startWhen, function(e){

     t.longPress(e, t.direction );

    }).bind(endWhen, function(e){

     t.mouseupFun(e, t.direction );

    });

    //注册鼠标滚动事件
    // FF
    if(document.addEventListener){
     document.addEventListener('DOMMouseScroll',t.mouseRuning,false);
    }

    //其它浏览器
    document.onmousewheel = t.mouseRuning;
   }
  },

  //鼠标滚动
  mouseRuning: function(e) {

   var t = simulation;

   e = e || window.event;

   //ie、FF
   if (e.detail) {
    if (e.detail < 0) {

     t._turnOf = 'forward';

     t.direction ();

    } else{

     t._turnOf = null;
     t.direction ();
    }
   // chrome
   } else if(e.wheelDelta) {

    if (e.wheelDelta > 0) {

     t._turnOf = 'forward';

     t.direction ();

    } else{

     t._turnOf = null;
     t.direction ();

    }
   } 
  },

  //判断是否长点击
  longPress: function(e, moveFun ) {

   var t = this;

   if ( u.match(/\b(Windows\sNT|Macintosh)\b/) ) {
    e = e || window.event;

    // 限制为鼠标左键点击才触发
    if (/^mouse/.test(e.type) && e.which !== 1) {
     return;
    }
   }

   t._setintervalId = setInterval(function(){

    t._mousedownTimer += 10;

    if( t._mousedownTimer >= 100 ){

     moveFun();
    }

   },20);
  },

  mouseupFun: function(e, moveFun) {
   
   var t = this;

   if ( u.match(/\b(Windows\sNT|Macintosh)\b/) ) {
    e = e || window.event;

    // 限制为鼠标左键点击才触发
    if (/^mouse/.test(e.type) && e.which !== 1) {
     return;
    }
   }

   clearTimeout(t._setintervalId);

   if( t._mousedownTimer < 100 ) {

    moveFun();
   }

   t._mousedownTimer = 0;
  },

  direction:function() {
   var t = simulation,
    barTop = t._scroll.position().top,
    pageTop = t._wapper.position().top,
    moveDistance = {};

    if ( t._turnOf === 'forward') {

     //页面到顶，不执行任何操作
     if (barTop == 0) {
      return;
     }

     moveDistance = {
      page: pageTop + t._distance,
      bar: barTop - parameter.scrollDistance
     }

     //如果滚动条距离顶部的距离少 < 每次滚动的距离，或者已经滚动到顶部，则不再滚动
     if(barTop < parameter.scrollDistance || barTop <= 0){

      moveDistance = {
       page: 0,
       bar: 0
      }
     }

    } else {

     //页面到底，不执行任何操作
     if (barTop == parameter.barArea - parameter.scrollHeight){
      return;
     }

     moveDistance = {
      page: pageTop - t._distance,
      bar: barTop + parameter.scrollDistance
     };

     // 如果滚动条距离底部的距离值 < 每次滚动的距离 或者已经到底部，则一次滚到底
     if ( moveDistance.bar + parameter.scrollHeight >= parameter.barArea) {

      moveDistance = {
       page: parameter.view - parameter.page,
       bar: parameter.barArea - parameter.scrollHeight
      };

     }
    }

    t._scroll.css({top: moveDistance.bar});
    t._wapper.css({top: moveDistance.page}); 
  },

  //拖动滚动条
  liveEvent: function() {
   var t = this,
    draging = false,
    currentY = 0,
    lastY = 0,
    pageY = 0; 

   //检测设备类型
   var _ua = function(e) {

    var Pos = null;

    if ( u.match(/\b(Windows\sNT|Macintosh)\b/) ) {
     e = e || window.event;

     // 限制为鼠标左键点击才触发
     if (/^mouse/.test(e.type) && e.which !== 1) {
      return;
     }

     Pos = {
      left : e.pageX,
      top: e.pageY
     }

    } else {
     Pos = {
      left : e.originalEvent.targetTouches[0].pageX,
      top: e.originalEvent.targetTouches[0].pageY
     }
    }
    return Pos;
   };

   var _start = function(e) {

    //监控鼠标
    e.preventDefault();

    if (t._scroll.get(0).setCapture) {
     t._scroll.get(0).setCapture();
    }

    draging = true;

    //记录当前滚动条的坐标
    lastY = t._scroll.position().top; 

    //记录按下鼠标的坐标
    pageY = _ua(e).top;
   };

   var _drag = function(e) {

    if( draging ) {

     var pageTop = t._wapper.position().top;
     var barTop = t._scroll.position().top;

     //滚动条每移动1px，页面相对滚动Npx 再 * 当前滚动条的到顶部的距离
     var pageMoveDistance = -(parameter.page / (parameter.barArea / 1)) * barTop;

     if (lastY + ( _ua(e).top - pageY ) < 0) {
      currentY = 0;
      pageMoveDistance = 0;

     } else if( lastY + ( _ua(e).top - pageY) + parameter.scrollHeight >= parameter.barArea) {
      currentY = parameter.barArea - parameter.scrollHeight;
      pageMoveDistance = parameter.view - parameter.page;
     }
     else {
      currentY = lastY + ( _ua(e).top - pageY);
     }

     t._scroll.css({ top:currentY});
     t._wapper.css({top: pageMoveDistance}); 
    }
   };

   var _end = function(e) {

    if (draging) {

     draging = false;

     //在IE下释放对鼠标的控制
     if (t._scroll.get(0).setCapture) {
      t._scroll.get(0).releaseCapture();
     }
     
     document.onmousemove = null;
     document.onmouseup = null;
    }
   };

   t._scroll.bind( startWhen, _start );

   t._wapper.bind( startWhen, _start );

   $(document).bind( moveWhen, _drag );
   
   $(document).bind( endWhen, _end );

   $(document).bind('blur', _end);
  }
 }
 return simulation;
});