simpletreemenu.js

var persisteduls=new Object()
var ddtreemenu=new Object()

ddtreemenu.closefolder="closed.gif" //set image path to "closed" folder image
ddtreemenu.openfolder="open.gif" //set image path to "open" folder image

//////////No need to edit beyond here///////////////////////////

ddtreemenu.createTree=function(treeid, enablepersist, persistdays){
var ultags=document.getElementById(treeid).getElementsByTagName("ul")
if (typeof persisteduls[treeid]=="undefined")
persisteduls[treeid]=(enablepersist==true && ddtreemenu.getCookie(treeid)!="")? ddtreemenu.getCookie(treeid).split(",") : ""
for (var i=0; i<ultags.length; i++)
ddtreemenu.buildSubTree(treeid, ultags[i], i)
if (enablepersist==true){ //if enable persist feature
var durationdays=(typeof persistdays=="undefined")? 1 : parseInt(persistdays)
ddtreemenu.dotask(window, function(){ddtreemenu.rememberstate(treeid, durationdays)}, "unload") //save opened UL indexes on body unload
}
}

ddtreemenu.buildSubTree=function(treeid, ulelement, index){
ulelement.parentNode.className="submenu"
if (typeof persisteduls[treeid]=="object"){ //if cookie exists (persisteduls[treeid] is an array versus "" string)
if (ddtreemenu.searcharray(persisteduls[treeid], index)){
ulelement.setAttribute("rel", "open")
ulelement.style.display="block"
ulelement.parentNode.style.borderLeftStyle="url("+ddtreemenu.openfolder+")"
}
else
ulelement.setAttribute("rel", "closed")
} //end cookie persist code
else if (ulelement.getAttribute("rel")==null || ulelement.getAttribute("rel")==false) //if no cookie and UL has NO rel attribute explicted added by user
ulelement.setAttribute("rel", "closed")
else if (ulelement.getAttribute("rel")=="open") //else if no cookie and this UL has an explicit rel value of "open"
ddtreemenu.expandSubTree(treeid, ulelement) //expand this UL plus all parent ULs (so the most inner UL is revealed!)
ulelement.parentNode.onclick=function(e){
var submenu=this.getElementsByTagName("ul")[0]
if (submenu.getAttribute("rel")=="closed"){
submenu.style.display="block"
submenu.setAttribute("rel", "open")
ulelement.parentNode.style.borderLeftStyle="dotted"
}
else if (submenu.getAttribute("rel")=="open"){
submenu.style.display="none"
submenu.setAttribute("rel", "closed")
ulelement.parentNode.style.borderLeftStyle="solid"
}
ddtreemenu.preventpropagate(e)
}
ulelement.onclick=function(e){
ddtreemenu.preventpropagate(e)
}
}

ddtreemenu.expandSubTree=function(treeid, ulelement){ //expand a UL element and any of its parent ULs
var rootnode=document.getElementById(treeid)
var currentnode=ulelement
currentnode.style.display="block"
currentnode.parentNode.style.borderLeftStyle="dotted"
while (currentnode!=rootnode){
if (currentnode.tagName=="UL"){ //if parent node is a UL, expand it too
currentnode.style.display="block"
currentnode.setAttribute("rel", "open") //indicate it's open
currentnode.parentNode.style.borderLeftStyle="dotted"
}
currentnode=currentnode.parentNode
}
}

ddtreemenu.flatten=function(treeid, action){ //expand or contract all UL elements
var ultags=document.getElementById(treeid).getElementsByTagName("ul")
for (var i=0; i<ultags.length; i++){
ultags[i].style.display=(action=="expand")? "block" : "none"
var relvalue=(action=="expand")? "open" : "closed"
ultags[i].setAttribute("rel", relvalue)
ultags[i].parentNode.style.borderLeftStyle=(action=="expand")? "dotted" : "solid"
}
}

ddtreemenu.rememberstate=function(treeid, durationdays){ //store index of opened ULs relative to other ULs in Tree into cookie
var ultags=document.getElementById(treeid).getElementsByTagName("ul")
var openuls=new Array()
for (var i=0; i<ultags.length; i++){
if (ultags[i].getAttribute("rel")=="open")
openuls[openuls.length]=i //save the index of the opened UL (relative to the entire list of ULs) as an array element
}
if (openuls.length==0) //if there are no opened ULs to save/persist
openuls[0]="none open" //set array value to string to simply indicate all ULs should persist with state being closed
ddtreemenu.setCookie(treeid, openuls.join(","), durationdays) //populate cookie with value treeid=1,2,3 etc (where 1,2... are the indexes of the opened ULs)
}

////A few utility functions below//////////////////////

ddtreemenu.getCookie=function(Name){ //get cookie value
var re=new RegExp(Name+"=[^;]+", "i"); //construct RE to search for target name/value pair
if (document.cookie.match(re)) //if cookie found
return document.cookie.match(re)[0].split("=")[1] //return its value
return ""
}

ddtreemenu.setCookie=function(name, value, days){ //set cookei value
var expireDate = new Date()
//set "expstring" to either future or past date, to set or delete cookie, respectively
var expstring=expireDate.setDate(expireDate.getDate()+parseInt(days))
document.cookie = name+"="+value+"; expires="+expireDate.toGMTString()+"; path=/";
}

ddtreemenu.searcharray=function(thearray, value){ //searches an array for the entered value. If found, delete value from array
var isfound=false
for (var i=0; i<thearray.length; i++){
if (thearray[i]==value){
isfound=true
thearray.shift() //delete this element from array for efficiency sake
break
}
}
return isfound
}

ddtreemenu.preventpropagate=function(e){ //prevent action from bubbling upwards
if (typeof e!="undefined")
e.stopPropagation()
else
event.cancelBubble=true
}

ddtreemenu.dotask=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)
}