Create a Drop-Down list using JavaScript and CSS

Requirements
Ability to change your MediaWiki:Common.js and MediaWiki:Monobook.css

Common.js Code
/* Any JavaScript here will be loaded for all users on every page load. */

function ddm {

// Variables, change these in case you need to set other class names (mmhide_ for // contribute users for example) var parentClass='isParent';	 //gets applied when the LI has a nested UL var activeParentClass='isActive';	 //gets applied when the nested UL is visible var preventHoverClass='nohover';	 //denotes a navigation that should not get any hover effects var indicateJSClass='dhtml';	 //gets applied to the main navigation when Javascript is available var toHideClass='hiddenChild';	 //gets applied to hide the nested UL var toShowClass='shownChild';	 //gets applied to show the nested UL var currentClass='current';	 //denotes the current active sub element and prevents collapsing var d=document.getElementById('nav');	//denotes the navigation element

// if DOM is not available stop right here. if(!document.getElementById && !document.createTextNode){return;}

// if the navigation element is available, apply the class denoting DHTML capabilities if(d) { d.className+=d.className==''?indicateJSClass:' '+indicateJSClass; var lis,i,firstUL,j,apply;

// loop through all LIs and check which ones have a nested UL lis=d.getElementsByTagName('li'); for(i=0;i<lis.length;i++) { firstUL=lis[i].getElementsByTagName('ul')[0] // if there is a nested UL, deactivate the first nested link and apply the class to show // there is a nested list if(firstUL) { lis[i].childNodes[0].onclick=function{return false;} lis[i].className+=lis[i].className==''?parentClass:' '+parentClass; // check if there is a "current" element apply=true; if(new RegExp('\\b'+currentClass+'\\b').test(lis[i].className)){apply=false;} if(apply) { for(j=0;j<firstUL.getElementsByTagName('li').lengt h;j++) { if(new RegExp('\\b'+currentClass+'\\b').test(firstUL.getE lementsByTagName('li')[j].className)){apply=false;break} } } // if there is no current element, apply the class to hide the nested list if(apply) { firstUL.className+=firstUL.className==''?toHideCla ss:' '+toHideClass; // check if there is a class to prevent hover effects and only apply the function // onclick if that is the case, otherwise apply it onclick and onhover if(new RegExp('\\b'+preventHoverClass+'\\b').test(d.class Name)) { lis[i].onclick=function{doddm(this);} } else { lis[i].onclick=function{doddm(this);} lis[i].onmouseover=function{doddm(this);} lis[i].onmouseout=function{doddm(null);} } // if there is a current element, define the list as being kept open and apply the // classes to show the nested list and define the parent LI as an active one } else { lis[i].keepopen=1; firstUL.className+=firstUL.className==''?toShowCla ss:' '+toShowClass; lis[i].className=lis[i].className.replace(parentClass,activeParentClass); } } } } // function to show and hide the nested lists and add the classes to the parent LIs function doddm(o) { var childUL,isobj,swap;

// loop through all LIs of the navigation lis=d.getElementsByTagName('li'); for(i=0;i<lis.length;i++) { isobj=lis[i]==o; // function to exchange class names in an object swap=function(tmpobj,tmporg,tmprep) { tmpobj.className=tmpobj.className.replace(tmporg,t mprep) } // if the current LI does not have an indicator to be kept visible if(!lis[i].keepopen) { childUL=lis[i].getElementsByTagName('ul')[0]; // check if there is a nested UL and if the current LI is not the one clicked on // and exchange the classes accordingly (ie. hide all other nested lists and // make the LIs parent rather than active. if(childUL)	{	if(new RegExp('\\b'+preventHoverClass+'\\b').test(d.class Name)) { if(new RegExp('\\b'+activeParentClass+'\\b').test(lis[i].className)) { swap(childUL,isobj?toShowClass:toHideClass,isobj?t oHideClass:toShowClass);	swap(lis[i],isobj?activeParentClass:parentClass,isobj?parentC lass:activeParentClass);	} else {

swap(childUL,isobj?toHideClass:toShowClass,isobj?t oShowClass:toHideClass); swap(lis[i],isobj?parentClass:activeParentClass,isobj?activeP arentClass:parentClass); } } else { swap(childUL,isobj?toHideClass:toShowClass,isobj?t oShowClass:toHideClass); swap(lis[i],isobj?parentClass:activeParentClass,isobj?activeP arentClass:parentClass); } } } } } } window.onload=function { ddm; // add other functions to be called onload below }

Monobook.css
/*Main Line Not Just Link Margin - From left Side*/ ul#nav{ margin:3; padding:2; list-style-type:none; border:none; background:#fff; padding:.5em; width:auto; } /*Drop Menu Line Colors that "flash" to load Menu*/ ul#nav li ul{ background:#fff; margin:0; padding:5; width:auto; } ul#nav li{ position:relative; margin:5; width:auto; padding:5; list-style-type:none; background:333; color:#333; line-height:150%; } /*Main Link Font Color and "loading border" set to fff for invisibility*/ ul#nav a{ border:1px solid #fff; color:#333; text-decoration:none; display:block; } /*Mouse over option text color*/ ul#nav a:hover{ border:1px inset #333; background:#333; color:#333; } /*Color of Text option drop down without mouse on them.*/ ul#nav li li a{ padding-left:1em; color:#006AFF; text-decoration:none; display:block; } ul#nav li li a:hover{ background:#cef; }

/* DDM relative dropdown example */ .hiddenChild{ position: absolute; left: -999em; } .shownChild{ left:-1px; } p{ clear:both;float:none; } /*Parent initial border information white fff set to hide "optional options area"*/ ul#nav.dhtml{ list-style-image: none; display: block; position:relative; width:auto; border:2px solid #fff; background:#333 margin:2; padding:2; list-style-type:none; height:1.5em; } /*WIDTH IS TOP OPTION WIDTH. (OPTION WIDTH - 1)*/ ul#nav.dhtml li{ position:relative; float:left; width:9em; border-right:1px solid #333; border-top:1px solid #333; border-left:1px solid #333; border-bottom:1px solid #333; } /*Initial background color of options with mouse hovered over main link*/ ul#nav.dhtml ul{ list-style-image: none; display: block; top:1.5em; position:absolute; border-top:1px solid #333; border-right:1px solid #333; border-left:1px solid #333; background:#333; width:auto; z-index:10; } ul#nav.dhtml li a,ul#nav.dhtml li a:hover{ border:none; background:#333; } ul#nav.dhtml li a{ padding:0 .5em; background:#333; } /*Options background color when main category is highlighted with mouse and options not selected WIDTH IS OPTIONS WIDTH*/ ul#nav.dhtml ul li{ border:none; width:9em; background:#fff; } /*No Mouse On Main Link Background*/ ul#nav.dhtml li.isParent{ background:#cef; } /*Yes Mouse On Main Link Background*/ ul#nav.dhtml li.isActive{ background:#fff; } ul#nav.dhtml li.isActive a{ background:cef; } ul#nav.dhtml li.isActive ul a{ padding:0 .5em; } ul#nav.dhtml a:hover{ background:#333; } ul#nav.dhtml li.isParent a:hover{ background:#333; } ul#nav.dhtml li.isActive ul a:hover{ background:#333; }

Code / Menu / Listing Used in Wiki Example
 NameofLink  Option1  Option2  Option3  Option4  Option5 

Thus creating a fully functional drop down list in your specified location.

Sample Code:  Shortcuts  Carnivores </li> Herbivores </li> Reptiles </li> Amphibians </li> Mammals </li></ul></li></ul></ul> Image of Sample Above on WikiMedia Forums: http://www.mwusers.com/forums/attachment.php?attachmentid=131&d=1234407968