Wicket autocompletion improvements

Here is how I extended Wicket's (version 1.2.2) autocompletion with 2 new features:
- immediatate open of the drop-down as soon as the text field gets focus
- define the width of the drop-down independent of the text field

As the JavaScript is well hidden within Wicket and is not easy to extend, I tried another approach that worked well. I created the package wicket.extensions.ajax.markup.html.autocomplete and placed my own edit of wicket-autocomplete.js. Because the package is compiled into my WAR I am sure it is the first on the classpath.

First of all, in the initialize function I added the following fragment:

 if (obj.className.indexOf('immediateopen') != -1) {
     obj.onfocus=function(event){
         updateChoices();
         return null;
     }
 }

Secondly I changed function showAutoComplete to the following:

 function showAutoComplete(){
     var position=getPosition(wicketGet(elementId));
     var menu=getAutocompleteMenu();
     var input=wicketGet(elementId);
     var rem = input.className.match(/\bmenuwidth(\d+)\b/);
     var menuwidth = (rem == null) ? input.offsetWidth : rem[1];
     menu.show();
     menu.style.left=position[0]+'px'
     menu.style.top=(input.offsetHeight+position[1])+'px';
     menu.style.width=menuwidth+'px';
     visible=1;
     hideShowCovered();
 }

That's it. Its fully backward compatible, except that if you use the classes immediateopen or menuwidthXXX you'll get the new behavior. If you are lazy, you can download the complete file.

Example:

  <input class="inputcode immediateopen menuwidth300" type="text" />