滚动条(兼容火狐狸、IE、chrome)[同事修改jsScrollbar] _JavaScript

滚动条(兼容火狐、IE、chrome)[同事修改jsScrollbar]
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<style type="text/css">
*{ margin:0px; padding: 0px; list-style:none;}
.box { width:500px; margin:0 auto; position:relative; top:100px;  }
.Container { position: absolute; top:0px; left: 100px; width: 400px; height: 200px; background-color: #EEE; }
#Scroller-1 {  position: absolute;  overflow: hidden; width: 400px; height: 200px; }
#Scroller-1 p { margin: 0; padding: 10px 20px; font-family: Verdana, Arial, Helvetica, sans-serif; font-size: 11px; text-indent: 20px; color: #777; }
.Scroller-Container { position: absolute; top: 0px; left: 0px; }
.Scrollbar-Track { width: 10px; height: 200px; position: absolute; top: 0px; right:0px; background-color: #EEE; cursor:pointer;  }
.Scrollbar-Handle { position: absolute; top: 0px; left: 0px; width: 10px; height: 30px; background-color: #CCC; }
</style>
<script type="text/javascript">
var scroller  = null;
var scrollbar = null;
window.onload = function () {
  scroller  = new jsScroller(document.getElementById("Scroller-1"), 400, 200);
  scrollbar = new jsScrollbar (document.getElementById("Scrollbar-Container"), scroller, false);
}


function jsScroller (o, w, h) {
	var self = this;
	var list = o.getElementsByTagName("div");
	for (var i = 0; i < list.length; i++) {
		if (list[i].className.indexOf("Scroller-Container") > -1) {
			o = list[i]; // 以 o 为对象，将对象包含的class名为Scroller-Container的元素付给 对象 o			
		}
	}
	
	//Private methods
	this._setPos = function (x, y) {
		if (x < this.viewableWidth - this.totalWidth) 
			x = this.viewableWidth - this.totalWidth;
		if (x > 0) x = 0;
		if (y < this.viewableHeight - this.totalHeight) 
			y = this.viewableHeight - this.totalHeight;
		if (y > 0) y = 0;
		this._x = x;
		this._y = y;
		with (o.style) {
			left = this._x +"px";
			top  = this._y +"px";
		}
	};
	
	//Public Methods
	this.reset = function () {
		this.content = o;
		this.totalHeight = o.offsetHeight;
		this.totalWidth	 = o.offsetWidth;
		this._x = 0;
		this._y = 0;
		with (o.style) {
			left = "0px";
			top  = "0px";
		}
	};
	this.scrollBy = function (x, y) {
		this._setPos(this._x + x, this._y + y);
	};
	this.scrollTo = function (x, y) {
		this._setPos(-x, -y);
	};
	this.stopScroll = function () {
		if (this.scrollTimer) window.clearInterval(this.scrollTimer);
	};
	this.startScroll = function (x, y) {
		this.stopScroll();
		this.scrollTimer = window.setInterval(
			function(){ self.scrollBy(x, y); }, 40
		);
	};
	this.swapContent = function (c, w, h) {
		o = c;
		var list = o.getElementsByTagName("div");
		for (var i = 0; i < list.length; i++) {
			if (list[i].className.indexOf("Scroller-Container") > -1) {
				o = list[i];
			}
		}
		if (w) this.viewableWidth  = w;
		if (h) this.viewableHeight = h;
		this.reset();
	};
	
	//variables
	this.content = o;
	this.viewableWidth  = w;
	this.viewableHeight = h;
	this.totalWidth	 = o.offsetWidth;
	this.totalHeight = o.offsetHeight;
	this.scrollTimer = null;
	this.reset();
};




function jsScrollbar (o, s, a, ev) {
	var self = this;
	
	this.reset = function () {
		//Arguments that were passed
		this._parent = o;
		this._src    = s;
		this.auto    = a ? a : false;
		this.eventHandler = ev ? ev : function () {};
		//Component Objects
		this._up   = this._findComponent("Scrollbar-Up", this._parent);
		this._down = this._findComponent("Scrollbar-Down", this._parent);
		this._yTrack  = this._findComponent("Scrollbar-Track", this._parent);
		this._yHandle = this._findComponent("Scrollbar-Handle", this._yTrack);
		//Height and position properties
		this._trackTop = findOffsetTop(this._yTrack);
		this._trackHeight  = this._yTrack.offsetHeight;
		this._handleHeight = this._yHandle.offsetHeight;
		this._x = 0;
		this._y = 0;
		//Misc. variables
		this._scrollDist  = 5;
		this._scrollTimer = null;
		this._selectFunc  = null;
		this._grabPoint   = null;
		this._tempTarget  = null;
		this._tempDistX   = 0;
		this._tempDistY   = 0;
		this._disabled    = false;
		this._ratio = (this._src.totalHeight - this._src.viewableHeight)/(this._trackHeight - this._handleHeight);
		
		this._yHandle.ondragstart  = function () {return false;};
		this._yHandle.onmousedown = function () {return false;};
		if(window.event){ 
			this._addEvent(this._src.content, "mousewheel", this._scrollbarWheel);			
		}//W3C 
		else{
			this._addEvent(this._src.content, "DOMMouseScroll", this._scrollbarWheel);
		}
		
		this._removeEvent(this._parent, "mousedown", this._scrollbarClick);
		this._addEvent(this._parent, "mousedown", this._scrollbarClick);
		
		this._src.reset();
		with (this._yHandle.style) {
			top  = "0px";
			left = "0px";
		}
		this._moveContent();
		
		if (this._src.totalHeight < this._src.viewableHeight) {
			this._disabled = true;
			this._yHandle.style.visibility = "hidden";
			if (this.auto) this._parent.style.visibility = "hidden";
		} else {
			this._disabled = false;
			this._yHandle.style.visibility = "visible";
			this._parent.style.visibility  = "visible";
		}
	};
	this._addEvent = function (o, t, f) {
		if (o.addEventListener) o.addEventListener(t, f, false);
		else if (o.attachEvent) o.attachEvent('on'+ t, f);
		else o['on'+ t] = f;
	};
	this._removeEvent = function (o, t, f) {
		if (o.removeEventListener) o.removeEventListener(t, f, false);
		else if (o.detachEvent) o.detachEvent('on'+ t, f);
		else o['on'+ t] = null;
	};
	this._findComponent = function (c, o) {
		var kids = o.childNodes;
		for (var i = 0; i < kids.length; i++) {
			if (kids[i].className && kids[i].className == c) {
				return kids[i];
			}
		}
	};
	//Thank you, Quirksmode
	function findOffsetTop (o) {
		var t = 0;
		if (o.offsetParent) {
			while (o.offsetParent) {
				t += o.offsetTop;
				o  = o.offsetParent;
			}
		}
		return t;
	};
	this._scrollbarClick = function (e) {
		if (self._disabled) return false;
		
		e = e ? e : event;
		if (!e.target) e.target = e.srcElement;
		
		if (e.target.className.indexOf("Scrollbar-Up") > -1) self._scrollUp(e);
		else if (e.target.className.indexOf("Scrollbar-Down") > -1) self._scrollDown(e);
		else if (e.target.className.indexOf("Scrollbar-Track") > -1) self._scrollTrack(e);
		else if (e.target.className.indexOf("Scrollbar-Handle") > -1) self._scrollHandle(e);
		
		self._tempTarget = e.target;
		self._selectFunc = document.onselectstart;
		document.onselectstart = function () {return false;};
		
		self.eventHandler(e.target, "mousedown");
		self._addEvent(document, "mouseup", self._stopScroll, false);
		
		return false;
	};
	this._scrollbarDrag = function (e) {
		e = e ? e : event;
		var t = parseInt(self._yHandle.style.top);
		var v = e.clientY + document.body.scrollTop - self._trackTop;
		with (self._yHandle.style) {
			if (v >= self._trackHeight - self._handleHeight + self._grabPoint)
				top = self._trackHeight - self._handleHeight +"px";
			else if (v <= self._grabPoint) top = "0px";
			else top = v - self._grabPoint +"px";
			self._y = parseInt(top);
		}
		
		self._moveContent();
	};
	this._scrollbarWheel = function (e) {
		e = e ? e : event;
		var dir = 0;
		if (e.wheelDelta >= 120) dir = -1;
		if (e.wheelDelta <= -120) dir = 1;
		if(e.detail >=3) dir= 1;
		if(e.detail <=-3) dir = -1;
		
		self.scrollBy(0, dir * 20);
		e.returnValue = false;
	};
	this._startScroll = function (x, y) {
		this._tempDistX = x;
		this._tempDistY = y;
		this._scrollTimer = window.setInterval(function () {
			self.scrollBy(self._tempDistX, self._tempDistY); 
		}, 40);
	};
	this._stopScroll = function () {
		self._removeEvent(document, "mousemove", self._scrollbarDrag, false);
		self._removeEvent(document, "mouseup", self._stopScroll, false);
		
		if (self._selectFunc) document.onselectstart = self._selectFunc;
		else document.onselectstart = function () { return true; };
		
		if (self._scrollTimer) window.clearInterval(self._scrollTimer);
		self.eventHandler (self._tempTarget, "mouseup");
	};
	this._scrollUp = function (e) {this._startScroll(0, -this._scrollDist);};
	this._scrollDown = function (e) {this._startScroll(0, this._scrollDist);};
	this._scrollTrack = function (e) {
		var curY = e.clientY + document.body.scrollTop;
		this._scroll(0, curY - this._trackTop - this._handleHeight/2);
	};
	this._scrollHandle = function (e) {
		var curY = e.clientY + document.body.scrollTop;
		this._grabPoint = curY - findOffsetTop(this._yHandle);
		this._addEvent(document, "mousemove", this._scrollbarDrag, false);
	};
	this._scroll = function (x, y) {
		if (y > this._trackHeight - this._handleHeight) 
			y = this._trackHeight - this._handleHeight;
		if (y < 0) y = 0;
		
		this._yHandle.style.top = y +"px";
		this._y = y;
		
		this._moveContent();
	};
	this._moveContent = function () {
		this._src.scrollTo(0, Math.round(this._y * this._ratio));
	};
	
	this.scrollBy = function (x, y) {
		this._scroll(0, (-this._src._y + y)/this._ratio);
	};
	this.scrollTo = function (x, y) {
		this._scroll(0, y/this._ratio);
	};
	this.swapContent = function (o, w, h) {// 判断浏览器
		if(window.event){ 
			this._removeEvent(this._src.content, "mousewheel", this._scrollbarWheel, false);
		}//W3C 
		else{
			this._removeEvent(this._src.content, "DOMMouseScroll", this._scrollbarWheel, false);
		}
		
		this._src.swapContent(o, w, h);
		this.reset();
	};
	
	this.reset();
};

</script>
</head>

<body>

<div class="box">
    <div class="Container">
      <div id="Scroller-1">
       <div style="left: 0px; top: -596px;" class="Scroller-Container">
          <p>Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Donec
     iaculis, ante et congue feugiat, elit wisi commodo metus, ut commodo 
    ligula enim ac justo. Pellentesque id ligula. Class aptent taciti 
    sociosqu ad litora torquent per conubia nostra, per inceptos hymenaeos. 
    Phasellus vitae mi a elit dictum volutpat. Pellentesque nec arcu. Etiam 
    blandit. Phasellus egestas dolor ut lacus. Sed enim justo, sagittis ut, 
    condimentum non, ullamcorper eu, neque. In hac habitasse platea 
    dictumst. Integer ipsum risus, sagittis ac, imperdiet ac, interdum sed, 
    libero. Praesent commodo. Mauris congue, urna eget hendrerit elementum, 
    dolor ligula ultrices neque, in elementum ante erat et elit.</p>
          <p>Vivamus vehicula. Integer cursus massa et nisl. Morbi pretium 
    sem eget risus. Vestibulum nec est. Donec feugiat purus et ligula. 
    Quisque semper. Sed eu ante. Curabitur suscipit porttitor libero. Nam 
    eros leo, sollicitudin eget, tincidunt vitae, facilisis a, dui. Proin 
    neque. Aliquam erat volutpat. Pellentesque felis.</p>
          <p>Aliquam consequat. Proin feugiat ultricies dui. Suspendisse 
    mollis dui nec nunc. Nam tristique, ante vitae imperdiet vestibulum, 
    elit nulla rhoncus nisl, vitae tincidunt dolor dui eu mi. In hac 
    habitasse platea dictumst. Nunc blandit dolor vel mauris. Proin wisi. 
    Nam pharetra ultrices tellus. Sed arcu. Lorem ipsum dolor sit amet, 
    consectetuer adipiscing elit. Nullam ultricies semper wisi. Sed nisl. 
    Donec blandit. Nunc vitae urna sed nisl mattis ornare.</p>
          <p>Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Donec
     iaculis, ante et congue feugiat, elit wisi commodo metus, ut commodo 
    ligula enim ac justo. Pellentesque id ligula. Class aptent taciti 
    sociosqu ad litora torquent per conubia nostra, per inceptos hymenaeos. 
    Phasellus vitae mi a elit dictum volutpat. Pellentesque nec arcu. Etiam 
    blandit. Phasellus egestas dolor ut lacus. Sed enim justo, sagittis ut, 
    condimentum non, ullamcorper eu, neque. In hac habitasse platea 
    dictumst. Integer ipsum risus, sagittis ac, imperdiet ac, interdum sed, 
    libero. Praesent commodo. Mauris congue, urna eget hendrerit elementum, 
    dolor ligula ultrices neque, in elementum ante erat et elit.</p>
          <p>Vivamus vehicula. Integer cursus massa et nisl. Morbi pretium 
    sem eget risus. Vestibulum nec est. Donec feugiat purus et ligula. 
    Quisque semper. Sed eu ante. Curabitur suscipit porttitor libero. Nam 
    eros leo, sollicitudin eget, tincidunt vitae, facilisis a, dui. Proin 
    neque. Aliquam erat volutpat. Pellentesque felis.</p>
          <p>Aliquam consequat. Proin feugiat ultricies dui. Suspendisse 
    mollis dui nec nunc. Nam tristique, ante vitae imperdiet vestibulum, 
    elit nulla rhoncus nisl, vitae tincidunt dolor dui eu mi. In hac 
    habitasse platea dictumst. Nunc blandit dolor vel mauris. Proin wisi. 
    Nam pharetra ultrices tellus. Sed arcu. Lorem ipsum dolor sit amet, 
    consectetuer adipiscing elit. Nullam ultricies semper wisi. Sed nisl. 
    Donec blandit. Nunc vitae urna sed nisl mattis ornare.</p>
        </div>
      </div>
    </div>
  <div style="visibility: visible;" id="Scrollbar-Container">
    <div class="Scrollbar-Track">
      <div style="top: 70px; left: 0px; visibility: visible;" class="Scrollbar-Handle"></div>
    </div>
  </div>
</div>


</body>

</html>