/********************************
 * @File:bannerMenu.js
 * @Description: 栏目多层菜单
 * @Date:2007-6-12
 * @version v1.0
 * @Copyright:wish
 * @create:ffw_cn
 ********************************/
//<--begin
var cssdropdown=
{
	disappeardelay: 200, //set delay in miliseconds before menu disappears onmouseout
	//No need to edit beyond here////////////////////////
	dropmenuobj: null, ie: document.all, firefox: document.getElementById&&!document.all,
	getposOffset:function(what, offsettype)
	{
		var totaloffset=(offsettype=="left")? what.offsetLeft : what.offsetTop;
		var parentEl=what.offsetParent;
		while (parentEl!=null)
		{
			totaloffset=(offsettype=="left")? totaloffset+parentEl.offsetLeft : totaloffset+parentEl.offsetTop;
			parentEl=parentEl.offsetParent;
		}
		return totaloffset;
	},
	
	showhide:function(obj, e, visible, hidden)
	{
		if (this.ie || this.firefox)
			this.dropmenuobj.style.left=this.dropmenuobj.style.top="-500px";
		if (e.type=="click" && obj.visibility=="hidden" || e.type=="mouseover")
			obj.visibility="visible";
		else if (e.type=="click")
			obj.visibility="hidden";
	},
	
	iecompattest:function()
	{
		return (document.compatMode && document.compatMode!="BackCompat")? document.documentElement : document.body
	},
	
	clearbrowseredge:function(obj, whichedge)
	{
		var edgeoffset=0;
		if (whichedge=="rightedge")
		{
			var windowedge=this.ie && !window.opera? this.iecompattest().scrollLeft+this.iecompattest().clientWidth-15 : window.pageXOffset+window.innerWidth-15
			this.dropmenuobj.contentmeasure=this.dropmenuobj.offsetWidth;
			if (windowedge-this.dropmenuobj.x < this.dropmenuobj.contentmeasure)  //move menu to the left?
				edgeoffset=this.dropmenuobj.contentmeasure-obj.offsetWidth;
		}
		else
		{
			var topedge=this.ie && !window.opera? this.iecompattest().scrollTop : window.pageYOffset;
			var windowedge=this.ie && !window.opera? this.iecompattest().scrollTop+this.iecompattest().clientHeight-15 : window.pageYOffset+window.innerHeight-18
			this.dropmenuobj.contentmeasure=this.dropmenuobj.offsetHeight;
			if (windowedge-this.dropmenuobj.y < this.dropmenuobj.contentmeasure)
			{ //move up?
				edgeoffset=this.dropmenuobj.contentmeasure+obj.offsetHeight;
				if ((this.dropmenuobj.y-topedge)<this.dropmenuobj.contentmeasure) //up no good either?
					edgeoffset=this.dropmenuobj.y+obj.offsetHeight-topedge;
			}
		}
		return edgeoffset
	},
	
	dropit:function(obj, e, dropmenuID)
	{
		if (this.dropmenuobj!=null) //hide previous menu
			this.dropmenuobj.style.visibility="hidden";
		this.clearhidemenu()
		if (this.ie||this.firefox)
		{
			obj.onmouseout=function(){cssdropdown.delayhidemenu()}
			this.dropmenuobj=document.getElementById(dropmenuID)
			this.dropmenuobj.onmouseover=function(){cssdropdown.clearhidemenu()}
			this.dropmenuobj.onmouseout=function(){cssdropdown.dynamichide(e)}
			this.dropmenuobj.onclick=function(){cssdropdown.delayhidemenu()}
			this.showhide(this.dropmenuobj.style, e, "visible", "hidden");
			this.dropmenuobj.x=this.getposOffset(obj, "left");
			this.dropmenuobj.y=this.getposOffset(obj, "top");
			this.dropmenuobj.style.left=this.dropmenuobj.x-this.clearbrowseredge(obj, "rightedge")+"px";
			this.dropmenuobj.style.top=this.dropmenuobj.y-this.clearbrowseredge(obj, "bottomedge")+obj.offsetHeight+1+"px";
		}
	},
	
	contains_firefox:function(a, b) 
	{
		while (b.parentNode)
		{
			if ((b = b.parentNode) == a)
				return true;
		}
		return false;
	},

	dynamichide:function(e)
	{
		/*
		var evtobj=window.event? window.event : e;
		if (this.ie&&!this.dropmenuobj.contains(evtobj.toElement))
		{
			alert("ie");
			this.delayhidemenu();
		}	
		else if (this.firefox&&e.currentTarget!= evtobj.relatedTarget&& !this.contains_firefox(evtobj.currentTarget, evtobj.relatedTarget))
		{
			alert("firefox");
			this.delayhidemenu();
		}
		*/
		this.delayhidemenu();
	},

	delayhidemenu:function()
	{
		this.delayhide=setTimeout("cssdropdown.dropmenuobj.style.visibility='hidden'",this.disappeardelay);
	},

	clearhidemenu:function()
	{
		if (this.delayhide!="undefined")
			clearTimeout(this.delayhide);
	}
}
//end-->