Cannot remove the latest element in grid model (grid in rod)

<zk>
<zscript><![CDATA[
import java.util.*;
import org.zkoss.zul.*;
import org.zkoss.zk.ui.event.*;
import org.zkoss.zk.ui.event.EventListener;

List list = new ArrayList();
for (int i = 0; i <200; i++)
list.add("remove " + i);

ListModelList model = new ListModelList(list);

RowRenderer renderer = new RowRenderer() {
public void render(Row row, Object data) throws Exception {
Button btn = new Button(String.valueOf(data));
btn.addEventListener(Events.ON_CLICK, new EventListener() {
public void onEvent(Event arg0) throws Exception {
((ListModelList)row.getGrid().getModel()).remove(data);
}
});
row.appendChild(btn);
}
};
]]></zscript>
<grid rowRenderer="${renderer}" model="${model}" width="300px" height="250px"/>
</zk>