Listbox autopaging and maximising screen use

<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"
	xsi:schemaLocation="http://www.zkoss.org/2005/zul http://www.zkoss.org/2005/zul/zul.xsd">

	<window  border="none" vflex="true" hflex="true">

		<style>

			.z-listbox-autopaging .z-listcell-cnt {
    				height: 15px;
    				overflow: hidden;
			}

		</style>

		<borderlayout vflex="true">
			<north  border="none" vflex="min">
				<div  height="25px" width="100%">
				</div>
			</north>

			<center  border="none" margins="0,0,0,0"
				hflex="true" vflex="min" autoscroll="true">
				<div >
					<groupbox >
						<caption label="CCCCCCC" ></caption>
						<tabbox  width="100%" style="padding: 0px">
							<tabs>
							<tab label="Tab1"></tab>
							</tabs>
							<tabpanels>
								<tabpanel vflex="min" style="overflow:auto;padding:0 0px;">
								
								<!--===============================================
								  Included window
								===================================================-->
								
								
<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"
	xsi:schemaLocation="http://www.zkoss.org/2005/zul
	http://www.zkoss.org/2005/zul/zul.xsd">

<!--===========================
    See http://www.zkoss.org/zkdemo/listbox/paging for BigList Code.
    
    import java.util.AbstractList;
 
public class BigList extends AbstractList<Integer> {
 
    private int _sz;
 
    public BigList(int sz) {
        if (sz < 0)
            throw new IllegalArgumentException("Negative not allowed: " + sz);
        _sz = sz;
    }
 
    public int size() {
        return _sz;
    }
 
    public Integer get(int j) {
        return Integer.valueOf(j);
    }
 
}
    
     
    ============================ -->
    
	<zscript><![CDATA[
        List items = new BigList(1000); //a big list of Integer
    ]]></zscript>
    
	<window id="incWindow"
		 border="none" hflex="true" vflex="min">

		<panel 
			title="inpanel" border="none" ></panel>

		<hbox align="stretch" pack="stretch" width="100%">

			<cell>
				<vbox align="stretch" pack="stretch" width="100%">
					<div >

			<listbox hflex="true" 
			multiple="false" mold="paging"  pagingPosition="top"  autopaging="true" >
			<listhead sizable="true">
				<listheader hflex="1" label="col1" ></listheader>
				<listheader hflex="1" label="col2" ></listheader>
				<listheader hflex="1" label="col3" ></listheader>
				<listheader hflex="1" label="col4" ></listheader>
			</listhead>
			
			<listitem forEach="${items}">
            	<listcell label="${each}-1" ></listcell>
            	<listcell label="${each}-2" ></listcell>
            	<listcell label="${each}-3" ></listcell>
            	<listcell label="${each}-4" ></listcell>
        	</listitem>
        
		</listbox>
					</div>

				</vbox>
			</cell>

		

		</hbox>


	</window>
</zk>							
								
								
								<!--===============================================
								  END Included window
								===================================================-->
								
								
								
								
								
								</tabpanel>
							</tabpanels>
						</tabbox>
					</groupbox>

				</div>
			</center>

			<south border="none" margins="1,0,0,0" height="25px" hflex="true">
				<div id="divSouth">
				</div>
			</south>
		</borderlayout>


	</window>

</zk>