Wicket ListMultipleChoice and ajax - wicket

Question

I have a question about the ListMultipleChoice, is there anyway to get the selected items before the submit by an ajax link for example because i wouldn't refresh my page every time.
Thanks!
// Liste des partenaires de l'offre.
final ListMultipleChoice partenairesSelec =
new ListMultipleChoice("partenairesSelec", new Model((Serializable) partenairesSelected), new PropertyModel(
offre,
"partenaires"), renderer);
// Liste des domaines.
final DropDownChoice makes = new DropDownChoice("domaines", new PropertyModel(this, "selectedMake"), makeChoices) {
#Override
protected CharSequence getDefaultChoice(Object selected) {
return new ArrayList<String>(modelsMap.keySet()).get(0);
}
};
// Liste des partenaires disponibles.
final ListMultipleChoice partenairesChoice =
new ListMultipleChoice("partenaires", new Model((Serializable) partenairesSelection), modelChoices, renderer);
// Action associé au changement du domaine.
makes.add(new AjaxFormComponentUpdatingBehavior("onchange") {
#Override
protected void onUpdate(AjaxRequestTarget target) {
target.addComponent(partenairesChoice);
}
});
// Bouton ajouter.
Button ajout = new Button("ajout") {
#Override
public void onSubmit() {
if (partenairesSelection.size() != 0) {
for (Partenaire p : partenairesSelection) {
if (!partenairesSelected.contains(p)) {
offre.getPartenaires().add(p);
modelsMap.get(selectedMake).remove(p);
}
}
offre.setPartenaires(sortPartenaireList(offre.getPartenaires()));
}
}
};
// Bouton supprimer.
Button suppr = new Button("suppr") {
#Override
public void onSubmit() {
List<Partenaire> tmp = new ArrayList<Partenaire>();
if (partenairesSelected.size() != 0) {
for (Partenaire p : partenairesSelected) {
if (!partenairesSelection.contains(p)) {
Long id = p.getPartnerDomainId();
tmp.add(p);
for (String key : modelsMap.keySet()) {
if (modelsMap.get(key).size() > 0 && modelsMap.get(key).get(0).getPartnerDomainId() == id) {
modelsMap.get(key).add(p);
}
}
}
}
for (Partenaire p : tmp) {
offre.getPartenaires().remove(p);
}
offre.setPartenaires(sortPartenaireList(offre.getPartenaires()));
}
}
};

Answer 1

AjaxFormChoiceComponentUpdatingBehavior is the class designed to do just that. Attach it to your component and you'll get AJAX updates wherever the selection changes.

Answer 2

AjaxFormChoiceComponentUpdatingBehavior does not work for ListMultipleChoice!
I also searched for a good working solution and after a while I found a really good tutorial facing exactly a situation with two ListMultipleChoice elements and add/remove buttons to exchange contents between the two multiple select boxes:
http://blog.xebia.com/2008/03/25/wicket-and-list-choice-transfers/
They use AjaxButtons for doing this without submitting the form.