ZK Chosenbox support item clicked event

CustomChosenbox.java

package test;

import org.zkoss.zk.ui.event.Events;
import org.zkoss.zkmax.zul.Chosenbox;

public class CustomChosenbox extends Chosenbox {

	private static final long serialVersionUID = -5929845559826449285L;
	static {
		addClientEvent(CustomChosenbox.class, "onItemClicked", CE_IMPORTANT | CE_DUPLICATE_IGNORE | CE_NON_DEFERRABLE);
	}
	public CustomChosenbox () {
		setWidgetOverride("doClick_", "function (evt) {\n"
				+"		this.$doClick_(evt);\n"
				+"		var $target = jq(evt.domTarget);\n"
				+"		if ($target.hasClass('z-chosenbox-sel-item-cnt'))\n"
				+"			this.fire('onItemClicked', {clickedItem: $target[0].innerHTML}, {toServer: true});\n"
				+"\n}");
	}

	public void service(org.zkoss.zk.au.AuRequest request, boolean everError) {
		final String cmd = request.getCommand();
		// process custom event
		if (cmd.equals("onItemClicked")) {
			Events.postEvent("onItemClicked", this, request.getData());
		} else {
			super.service(request, everError);
		}
	}
}

test.zul

<zk>
	<window id="win" apply="test.TestComposerTwo">
		<chosenbox id="cbx" use="test.CustomChosenbox"
			model="${win$composer.model}"/>
	</window>
</zk>

TestComposerTwo.java

package test;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import org.zkoss.zk.ui.event.Event;
import org.zkoss.zk.ui.select.SelectorComposer;
import org.zkoss.zk.ui.select.annotation.Listen;
import org.zkoss.zul.ListModel;
import org.zkoss.zul.ListModelList;

@SuppressWarnings("rawtypes")
public class TestComposerTwo extends SelectorComposer {

	private static final long serialVersionUID = -5358059094135126494L;
	private ListModelList _model;
	@SuppressWarnings("unchecked")
	public ListModel getModel () {
		if (_model == null) {
			List l = new ArrayList();
			l.add("item 1");
			l.add("item 2");
			l.add("item 3");
			_model = new ListModelList(l);
		}
		return _model;
	}
	@Listen(" onItemClicked = #cbx")
	public void doSomething (Event event) {
		System.out.println(((Map)event.getData()).get("clickedItem"));
	}
}