//Chrome Drop Down Menu v2.01- Author: Dynamic Drive (http://www.dynamicdrive.com)
//Last updated: November 14th 06- added iframe shim technique

var cssdropdown={
disappeardelay: 250, //set delay in miliseconds before menu disappears onmouseout
disablemenuclick: false, //when user clicks on a menu item with a drop down menu, disable menu item's link?
enableswipe: 1, //enable swipe effect? 1 for yes, 0 for no
enableiframeshim: 1, 
//enable "iframe shim" technique to get drop down menus to correctly appear on top of controls such as form objects in IE5.5/IE6? 1 for yes, 0 for no

//No need to edit beyond here////////////////////////
dropmenuobj: null, ie: document.all, firefox: document.getElementById&&!document.all, swipetimer: undefined, bottomclip:0,

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;
},

swipeeffect:function(){
  if (this.bottomclip<parseInt(this.dropmenuobj.offsetHeight)){
    this.bottomclip+=10+(this.bottomclip/10) //unclip drop down menu visibility gradually
    this.dropmenuobj.style.clip="rect(0 auto "+this.bottomclip+"px 0)"
  }
  else return
  this.swipetimer=setTimeout("cssdropdown.swipeeffect()", 5)
},

showhide:function(obj, e){
  if (this.ie || this.firefox)
    this.dropmenuobj.style.left=this.dropmenuobj.style.top="-500px"
  if (e.type=="click" && obj.visibility==hidden || e.type=="mouseover"){
    if (this.enableswipe==1){
      if (typeof this.swipetimer!="undefined")
        clearTimeout(this.swipetimer)
      obj.clip="rect(0 auto 0 0)" //hide menu via clipping
      this.bottomclip=0
      this.swipeeffect()
    }
    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
      edgeoffset=200 //added by doug to offset when not enough horizontal screenspace, original line of code above
  }
  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
        edgeoffset=0 //added by doug to offset when not enough horizontal screenspace, original line of code above
    }
  }
  return edgeoffset
},


// event function to show/hide dropdown menu 
dropit:function(obj, e, dropmenuID){
  if (this.dropmenuobj!=null) //hide previous menu
    this.dropmenuobj.style.visibility="hidden" //hide menu
  this.clearhidemenu()
  if (this.ie||this.firefox){
    obj.onmouseout=function(){cssdropdown.delayhidemenu()}
    obj.onclick=function(){return !cssdropdown.disablemenuclick} //disable main menu item link onclick?
    this.dropmenuobj=document.getElementById(dropmenuID)
    this.dropmenuobj.onmouseover=function(){cssdropdown.clearhidemenu()}
    this.dropmenuobj.onmouseout=function(e){cssdropdown.dynamichide(e)}
    this.dropmenuobj.onclick=function(){cssdropdown.delayhidemenu()}
    this.showhide(this.dropmenuobj.style, e)
    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"
    this.positionshim() //call iframe shim function
  }
},

positionshim:function(){ //display iframe shim function
  if (this.enableiframeshim && typeof this.shimobject!="undefined"){
    if (this.dropmenuobj.style.visibility=="visible"){
      this.shimobject.style.width=this.dropmenuobj.offsetWidth+"px"
      this.shimobject.style.height=this.dropmenuobj.offsetHeight+"px"
      this.shimobject.style.left=this.dropmenuobj.style.left
      this.shimobject.style.top=this.dropmenuobj.style.top
    }
    this.shimobject.style.display=(this.dropmenuobj.style.visibility=="visible")? "block" : "none"
  }
},

hideshim:function(){
  if (this.enableiframeshim && typeof this.shimobject!="undefined")
    this.shimobject.style.display='none'
},

// check if we are running in firefox
contains_firefox:function(a, b) {
while (b.parentNode)
  if ((b = b.parentNode) == a) return true;
  return false;
},
// hide function that chcecks for browser type
dynamichide:function(e){
  var evtobj=window.event? window.event : e
  if (this.ie&&!this.dropmenuobj.contains(evtobj.toElement))
    this.delayhidemenu()
  else if (this.firefox&&e.currentTarget!= evtobj.relatedTarget&& !this.contains_firefox(evtobj.currentTarget, evtobj.relatedTarget))
    this.delayhidemenu()
},

// delay function for a 'delayed hide' so user wont loose dropdown menu too easy 
delayhidemenu:function(){
  this.delayhide=setTimeout("cssdropdown.dropmenuobj.style.visibility='hidden'; cssdropdown.hideshim()",this.disappeardelay) //hide menu
},

clearhidemenu:function(){
if (this.delayhide!="undefined") clearTimeout(this.delayhide)
},
// function to initialize the menu
// as argument it takes the id of the menu area(s))
startchrome:function(){
  // for all arguments (=menu id's) do
  for (var ids=0; ids<arguments.length; ids++){
    // assign menuitems to the collection of a - tags of the given menu 
    var menuitems=document.getElementById(arguments[ids]).getElementsByTagName("a")
    // for all menu items do
    for (var i=0; i<menuitems.length; i++){
      // if menu item has an attribute "rel", i.e. a reference to the dropdown menu
      if (menuitems[i].getAttribute("rel")){
        var relvalue=menuitems[i].getAttribute("rel")
        // define the onmouseover event for the menu item, that is show the dropdown menu 
        menuitems[i].onmouseover=function(e){
          var event=typeof e!="undefined"? e : window.event
          cssdropdown.dropit(this,event,this.getAttribute("rel"))
        }
      }
    }
  }
  if (window.createPopup && !window.XmlHttpRequest){ //if IE5.5 to IE6, create iframe for iframe shim technique
    document.write('<IFRAME id="iframeshim"  src="" style="display: none; left: 0; top: 0; z-index: 90; position: absolute; filter: progid:DXImageTransform.Microsoft.Alpha(style=0,opacity=0)" frameBorder="0" scrolling="no"></IFRAME>')
  this.shimobject=document.getElementById("iframeshim") //reference iframe object
  }
}

}