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Since Wicket Ajax now register DOM events (like click, change, ...) instead of using inline attributes like onclick, onchange, ... there is no more a script to decorate. Instead the new implementation provides points to listen to:

• precondition - executed earlier. If it returns false then the Ajax call (and all handlers below) is not executed at all
• before handler - executed before the fire of the Ajax call
• after handler - executed after the fire of the Ajax call but before it returns ( if the Ajax call is asynchronous )then it is executed right after its firing. If it is synchronous then it is executed after the complete handler
• success handler - executed on successful return of the Ajax call
• failure handler - executed on unsuccessful return of the Ajax call
• complete handler - executed on both successful and unsuccessful return

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  protected void updateAjaxAttributes(AjaxRequestAttributes attributes)
  {
      super.updateAjaxAttributes(AjaxRequestAttributes attributes);

      AjaxCallListener myAjaxCallListener = new AjaxCallListener() {

        @Override public CharSequence getBeforeHandler(Component component) { return "alert('I\'m executed before the firing of the Ajax call')"; }
      };
      attributes.getAjaxCallListeners().add(myAjaxCallListener);
  }

There are also handy methods like onBefore(CharSequence), onComplete(CharSequence), ... but they do not provide access to the component which is bound with the Ajax behavior.

An Ajax request can have 0 or more IAjaxCallListener's.
o.a.w.ajax.attributes.AjaxCallListener is an adapter of IAjaxCallListener that implements all methods with noop bodies. If the body returns null or empty string then it is discarded.

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Those replaces the old Wicket.Ajax.(registerPreCallHandler|registerPostCallHandler|registerFailureHandler) methods and uses publish/subscribe mechanism.

Example (JavaScript):

    Wicket.Event.subscribe('/ajax/call/failure', function(jqEvent, errorThrownattributes, attributesjqXHR, jqXHRerrorThrown, textStatus) {
      // do something when an Ajax call fails
    });

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1. To run the Ajax tests see the description at the top of wicket-core/src/test/js/ajax.js. It is required to run them through Web Server

What parameters are passed to the handlers ?

1. before handler - attributes (the Ajax call attributes), jqXHR (the jQuery XMLHttpRequest object), settings (the jQuery ajax settings)
2. after handler - attributes
3. success handler - attributes, jqXHR, data (the response), textStatus (the response status)
4. failure handler - attributes, errorMessage (the error message from jQuery)
5. complete handler - attrs, jqXHR, textStatus

The global listeners receive the same parameters prepended by jqEvent. This is the event triggered by jQuery. See section Global Ajax call listeners above.