
function MM_swapImgRestore() { //v3.0
  var i,x,a=document.MM_sr; for(i=0;a&&i<a.length&&(x=a[i])&&x.oSrc;i++) x.src=x.oSrc;
}

function MM_preloadImages() { //v3.0
  var d=document; if(d.images){ if(!d.MM_p) d.MM_p=new Array();
    var i,j=d.MM_p.length,a=MM_preloadImages.arguments; for(i=0; i<a.length; i++)
    if (a[i].indexOf("#")!=0){ d.MM_p[j]=new Image; d.MM_p[j++].src=a[i];}}
}

function MM_findObj(n, d) { //v4.01
  var p,i,x;  if(!d) d=document; if((p=n.indexOf("?"))>0&&parent.frames.length) {
    d=parent.frames[n.substring(p+1)].document; n=n.substring(0,p);}
  if(!(x=d[n])&&d.all) x=d.all[n]; for (i=0;!x&&i<d.forms.length;i++) x=d.forms[i][n];
  for(i=0;!x&&d.layers&&i<d.layers.length;i++) x=MM_findObj(n,d.layers[i].document);
  if(!x && d.getElementById) x=d.getElementById(n); return x;
}

function MM_swapImage() { //v3.0
  var i,j=0,x,a=MM_swapImage.arguments; document.MM_sr=new Array; for(i=0;i<(a.length-2);i+=3)
   if ((x=MM_findObj(a[i]))!=null){document.MM_sr[j++]=x; if(!x.oSrc) x.oSrc=x.src; x.src=a[i+2];}
}


// Check Mouse Over/Out of Flash (Start)

function meunover() {
	document.getElementById("siteMenu").flashMenu_Over();
	}
function meunout() {
	document.getElementById("siteMenu").flashMenu_Out();
	}
document.getElementById("siteMenu");

// Check Mouse Over/Out of Flash (End)




// Check Screen Resolution for CopyRight & sitemap button (Start)

function checkScreenResolution() {
	if(screen.width = 800) {
  		document.getElementById("bottomDiv").style.width="760";   
	} else if (screen.width = 1024) {
		document.getElementById("bottomDiv").style.width="960";   
	} else if (screen.width > 1024) {
		document.getElementById("bottomDiv").style.width="50%";   
	}
}
// Check Screen Resolution for CopyRight & sitemap button (End)





////////////////////////////////////// Left Sub Menu //////////////////////////////////////


var disappeardelay=250  //menu disappear speed onMouseout (in miliseconds)
var enableanchorlink=0 //Enable or disable the anchor link when clicked on? (1=e, 0=d)
var hidemenu_onclick=1 //hide menu when user clicks within menu? (1=yes, 0=no)
var horizontaloffset=1 //horizontal offset of menu from default location. (0-5 is a good value)

/////No further editting needed

var ie5=document.all
var ns6=document.getElementById&&!document.all

function getposOffset(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;
}

function showhide(obj, e, visible, hidden){
if (ie5||ns6)
dropmenuobj.style.left=dropmenuobj.style.top=-500
if (e.type=="click" && obj.visibility==hidden || e.type=="mouseover")
obj.visibility=visible
else if (e.type=="click")
obj.visibility=hidden
}

function iecompattest(){
return (document.compatMode && document.compatMode!="BackCompat")? document.documentElement : document.body
}

function clearbrowseredge(obj, whichedge){
var edgeoffset=0
if (whichedge=="rightedge"){
var windowedge=ie5 && !window.opera? iecompattest().scrollLeft+iecompattest().clientWidth-15 : window.pageXOffset+window.innerWidth-15
dropmenuobj.contentmeasure=dropmenuobj.offsetWidth
if (windowedge-dropmenuobj.x-obj.offsetWidth < dropmenuobj.contentmeasure)
edgeoffset=dropmenuobj.contentmeasure+obj.offsetWidth+(horizontaloffset*2) //no space to the right of page? Move menu over to the left
}
else{
var topedge=ie5 && !window.opera? iecompattest().scrollTop : window.pageYOffset
var windowedge=ie5 && !window.opera? iecompattest().scrollTop+iecompattest().clientHeight-15 : window.pageYOffset+window.innerHeight-18
dropmenuobj.contentmeasure=dropmenuobj.offsetHeight
if (windowedge-dropmenuobj.y < dropmenuobj.contentmeasure){ //move menu up?
edgeoffset=dropmenuobj.contentmeasure-obj.offsetHeight
if ((dropmenuobj.y-topedge)<dropmenuobj.contentmeasure) //up no good either? (position at top of viewable window then)
edgeoffset=dropmenuobj.y
}
}
return edgeoffset
}

function dropdownmenu(obj, e, dropmenuID){
if (window.event) event.cancelBubble=true
else if (e.stopPropagation) e.stopPropagation()
if (typeof dropmenuobj!="undefined") //hide previous menu
dropmenuobj.style.visibility="hidden"
clearhidemenu()
if (ie5||ns6){
obj.onmouseout=delayhidemenu
dropmenuobj=document.getElementById(dropmenuID)
if (hidemenu_onclick) dropmenuobj.onclick=function(){dropmenuobj.style.visibility='hidden'}
dropmenuobj.onmouseover=clearhidemenu
dropmenuobj.onmouseout=ie5? function(){ dynamichide(event)} : function(event){ dynamichide(event)}
showhide(dropmenuobj.style, e, "visible", "hidden")
dropmenuobj.x=getposOffset(obj, "left")
dropmenuobj.y=getposOffset(obj, "top")
dropmenuobj.style.left=dropmenuobj.x-clearbrowseredge(obj, "rightedge")+obj.offsetWidth+horizontaloffset+"px"
dropmenuobj.style.top=dropmenuobj.y-clearbrowseredge(obj, "bottomedge")+"px"
}
return clickreturnvalue()
}

function clickreturnvalue(){
if ((ie5||ns6) && !enableanchorlink) return false
else return true
}

function contains_ns6(a, b) {
while (b.parentNode)
if ((b = b.parentNode) == a)
return true;
return false;
}

function dynamichide(e){
if (ie5&&!dropmenuobj.contains(e.toElement))
delayhidemenu()
else if (ns6&&e.currentTarget!= e.relatedTarget&& !contains_ns6(e.currentTarget, e.relatedTarget))
delayhidemenu()
}

function delayhidemenu(){
delayhide=setTimeout("dropmenuobj.style.visibility='hidden'",disappeardelay)
}

function clearhidemenu(){
if (typeof delayhide!="undefined")
clearTimeout(delayhide)
}
////////////////////////////////////// Left Sub Menu //////////////////////////////////////









////////////////////////////////////// Sub Menu 2 //////////////////////////////////////


var ddtabmenu={
	disabletablinks: false, //Disable hyperlinks in 1st level tabs with sub contents (true or false)?
	snap2original: [true, 300], //Should tab revert back to default selected when mouse moves out of menu? ([true/false, delay_millisec]

	currentpageurl: window.location.href.replace("http://"+window.location.hostname, "").replace(/^\//, ""), //get current page url (minus hostname, ie: http://www.dynamicdrive.com/)

definemenu:function(tabid, dselected){
	this[tabid+"-menuitems"]=null
	this[tabid+"-dselected"]=-1
	this.addEvent(window, function(){ddtabmenu.init(tabid, dselected)}, "load")
},

showsubmenu:function(tabid, targetitem){
	var menuitems=this[tabid+"-menuitems"]
	this.clearrevert2default(tabid)
 for (i=0; i<menuitems.length; i++){
		menuitems[i].className=""
		if (typeof menuitems[i].hasSubContent!="undefined")
			document.getElementById(menuitems[i].getAttribute("rel")).style.display="none"
	}
	targetitem.className="current"
	if (typeof targetitem.hasSubContent!="undefined")
		document.getElementById(targetitem.getAttribute("rel")).style.display="block"
},

isSelected:function(menuurl){
	var menuurl=menuurl.replace("http://"+menuurl.hostname, "").replace(/^\//, "")
	return (ddtabmenu.currentpageurl==menuurl)
},

isContained:function(m, e){
	var e=window.event || e
	var c=e.relatedTarget || ((e.type=="mouseover")? e.fromElement : e.toElement)
	while (c && c!=m)try {c=c.parentNode} catch(e){c=m}
	if (c==m)
		return true
	else
		return false
},

revert2default:function(outobj, tabid, e){
	if (!ddtabmenu.isContained(outobj, tabid, e)){
		window["hidetimer_"+tabid]=setTimeout(function(){
			ddtabmenu.showsubmenu(tabid, ddtabmenu[tabid+"-dselected"])
		}, ddtabmenu.snap2original[1])
	}
},

clearrevert2default:function(tabid){
 if (typeof window["hidetimer_"+tabid]!="undefined")
		clearTimeout(window["hidetimer_"+tabid])
},

addEvent:function(target, functionref, tasktype){ //assign a function to execute to an event handler (ie: onunload)
	var tasktype=(window.addEventListener)? tasktype : "on"+tasktype
	if (target.addEventListener)
		target.addEventListener(tasktype, functionref, false)
	else if (target.attachEvent)
		target.attachEvent(tasktype, functionref)
},

init:function(tabid, dselected){
	var menuitems=document.getElementById(tabid).getElementsByTagName("a")
	this[tabid+"-menuitems"]=menuitems
	for (var x=0; x<menuitems.length; x++){
		if (menuitems[x].getAttribute("rel")){
			this[tabid+"-menuitems"][x].hasSubContent=true
			if (ddtabmenu.disabletablinks)
				menuitems[x].onclick=function(){return false}
			if (ddtabmenu.snap2original[0]==true){
				var submenu=document.getElementById(menuitems[x].getAttribute("rel"))
				menuitems[x].onmouseout=function(e){ddtabmenu.revert2default(submenu, tabid, e)}
				submenu.onmouseover=function(){ddtabmenu.clearrevert2default(tabid)}
				submenu.onmouseout=function(e){ddtabmenu.revert2default(this, tabid, e)}
			}
		}
		else //for items without a submenu, add onMouseout effect
			menuitems[x].onmouseout=function(e){this.className=""; if (ddtabmenu.snap2original[0]==true) ddtabmenu.revert2default(this, tabid, e)}
		menuitems[x].onmouseover=function(){ddtabmenu.showsubmenu(tabid, this)}
		if (dselected=="auto" && typeof setalready=="undefined" && this.isSelected(menuitems[x].href)){
			ddtabmenu.showsubmenu(tabid, menuitems[x])
			this[tabid+"-dselected"]=menuitems[x]
			var setalready=true
		}
		else if (parseInt(dselected)==x){
			ddtabmenu.showsubmenu(tabid, menuitems[x])
			this[tabid+"-dselected"]=menuitems[x]
		}
	}
}
}
////////////////////////////////////// Sub Menu 2 //////////////////////////////////////


////////////////////////////////////// Code for Analysis Wrote by Ricky //////////////////////////////////////

var gaJsHost = (("https:" == document.location.protocol) ? "https://ssl." : "http://www.");
document.write(unescape("%3Cscript src='" + gaJsHost + "google-analytics.com/ga.js' type='text/javascript'%3E%3C/script%3E"));

try {
var pageTracker = _gat._getTracker("UA-9540387-1");
pageTracker._setDomainName(".plktkp.edu.hk");
pageTracker._trackPageview();
} catch(err) {}

////////////////////////////////////// Code for Analysis Wrote by Ricky //////////////////////////////////////
