Zkoss - componente listbox(listitem)

import java.util.List;

import org.zkoss.zul.ListModelList;
import org.zkoss.zul.Listbox;

@SuppressWarnings("serial")
public class YourListBox extends Listbox {
	private ListModelList modelList = new ListModelList();

	public void setData(List<Object> data) {

		this.modelList.addAll(data);

		super.setModel(modelList);
	}

	public void addItem(Object item) {
		if (!this.modelList.contains(item)) {
			this.modelList.add(item);
		}
	}

	public void removeItem(Object item) {
		this.modelList.remove(item);
	}

	public Object[] getData() {
		return this.modelList.toArray();
	}
}

listbox.getItemCount();

public class GListBox extends Listbox {
	private Object selected = null;
	private ListModelList modelList = new ListModelList();

	public void setData(List<Object> data) {

		this.modelList.addAll(data);
		
		super.addEventListener("onSelect", new EventListener() {
			public void onEvent(Event e) throws Exception {
				int index = GListBox.this.getSelectedIndex();
				if (index != -1) {
					selected = GListBox.this.modelList.get(index);
				}
			}
		});

		super.setModel(modelList);
	}

	public void addItem(Object item) {
		if (!this.modelList.contains(item)) {
			this.modelList.add(item);
		}
	}

	public void removeItem(Object item) {
		this.modelList.remove(item);
	}
	
	public Object getSelected() {
		return this.selected;
	}

	public Object[] getData() {
		return this.modelList.toArray();
	}
}

<?page id="pgLista" title="" cacheable="false" 
	language="xul/html" zscriptLanguage="Java" contentType="text/html;charset=UTF-8"?>

<zk xmlns="http://www.zkoss.org/2005/zul"
	xmlns:h="http://www.w3.org/1999/xhtml"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  
	<window id="controller"
		apply="controller.ListaController"
		title="TESTE" position="center" width="700px"
		border="normal" style="background-color:#FFFFFF">

		<listbox id="list" use="view.GListBox"
			height="250px" mold="paging" pageSize="14">
		</listbox>

		<button id="print" label="Imprimir" width="85px" height="24px"
			forward="onClick=onPrint" />

	</window>
</zk>

public class ListaController extends GenericAutowireComposer {
	protected GListBox list = null;

	private Window window = null;

	@Override
	public void doAfterCompose(Component cmp) throws Exception {

		List<Object> itens = new ArrayList<Object>(0);

		itens.add("Item 1");
		itens.add("Item 2");
		itens.add("Item 3");

		this.window = (Window) cmp;

		this.list = (GListBox) this.window.getFellow("list");

		this.list.setData(itens);

		ListitemRenderer renderer = new ListitemRenderer() {

			@Override
			public void render(Listitem listItem, Object data) throws Exception {
				String d = (String) data;

				new Listcell(d).setParent(listItem);
			}
		};

		this.list.setItemRenderer(renderer);

		super.doAfterCompose(cmp);
	}

	public void onPrint(Event event) throws Exception {

		for (Object item : this.list.getData()) {
			System.out.println("-->> " + item);
		}

		Messagebox.show("Impressão concluida!", "Mensagem", Messagebox.OK, Messagebox.INFORMATION);
	}
}

<zscript>
        public void showItem(){
            int index = 2; // 
            alert("item  selecionado >>> " + rowsEmails.selectedItem.children.get(index).label); // retorna a segunda coluna do intem selecionado do   listbox   
        }
</zscript>
no onSelect do listbox vc chama esse método

<?page title="new page title" contentType="text/html;charset=UTF-8"?>
<zk>
<window title="My First Window" border="normal">
<window>
<zscript>
	String[] lista = new String[1];
	lista[0] = "Item";
	
</zscript>
<listbox id="lbx" mold="paging" multiple="true">
<listitem forEach="${lista}">
	<listcell label="${each} - ColA"/>
	<listcell label="${each} - ColB"/>
	<listcell label="${each} - ColC"/>
</listitem>
</listbox>
<button label="show selected" onClick='alert(""+lbx.getSelectedItem().getChildren().get(2).getLabel())'/>
	<!-- Apenas mudar o get() para alterar entre as colunas -->
</window>
</window>	
</zk>