<zk>
	<zscript><![CDATA[
ListitemRenderer renderer = new ListitemRenderer(){

	public void render(Listitem item, Object data) throws Exception {
		item.appendChild(new Listcell("item"));
		item.appendChild(new Listcell("item"));
		item.appendChild(new Listcell("item"));
		
	}
	
};
	]]></zscript>
	<listbox height="500px" width="300px" id="lb" itemRenderer="${renderer}">
	<custom-attributes org.zkoss.zul.listbox.rod="false"/>
		<listhead>
			<listheader label="col" forEach="1,1,1"/>
		</listhead>
	</listbox>
	<timer repeats="true" running="true" delay="3000">
		<attribute name="onTimer"><![CDATA[
			List list = new ArrayList();
			
			for (int i = 0; i < 1000; i++)
				list.add("item");
			lb.setModel(new ListModelList(list));
		]]></attribute>
	</timer>
</zk>