getRequestCycleSettings().setGatherExtendedBrowserInfo(true);

This method works via a redirect to the BrowserInfoPage and finally it goes to your ‘original’ page. Because of this it is possible that you see the BrowserInfoPage very shortly especially on slow computers/browsers or internet connections. But what if you don’t want this and only want to know whether Javascript is enabled? Please read on…

When the page is rendered it does a call(back) to Wicket. If this callback is possible then we can assume Javascipt is enabled.

How to setup?

e.g. Login.java (Page)

final WebClientInfo clientInfo = (WebClientInfo) WebRequestCycle.get().getClientInfo();
final AbstractDefaultAjaxBehavior behavior = new AbstractDefaultAjaxBehavior()
   @Override
   protected void respond(final AjaxRequestTarget target) {
        if (target != null) {
            clientInfo.getProperties().setJavaEnabled(true);
        }
   }
};
add(behavior);

Label jsEnabledScript = new Label("jsEnabledScript", "wicketAjaxGet('"+ behavior.getCallbackUrl() +"', function() { }, function() { });");
jsEnabledScript.setEscapeModelStrings(false); // do not HTML escape JavaScript code
add(jsEnabledScript);

And in your HTML

<script type="text/javascript" wicket:id="jsEnabledScript"></script>

How to use?

final WebClientInfo clientInfo = (WebClientInfo) WebRequestCycle.get().getClientInfo();
boolean javascriptEnabled = clientInfo.getProperties().isJavaEnabled();

When you need to debug your application it is not very usefull to use the compressed one but in production it really is. To switch very easy from the compressed version to the ‘normal’ version and the other way around you can create a static variable where you define the location of the JavaScript file. Use the static variable to add the file to your page/header. Now you can switch versions (normal/compressed) by changing the static variable (in only one file).

JQuery.java:

public static final String JQUERY_BASE = "base/jquery-1.2.6.min.js";

(Wicket) Page:

add(HeaderContributor.forJavaScript(JQuery.class, JQuery.JQUERY_BASE));