final RequestLogVisualization viz = new RequestLogVisualization();
final RootLayoutPanel root = RootLayoutPanel.get();
root.add(viz);
root.setWidgetTopBottom(viz, 10, Unit.PX, 10, Unit.PX);
root.setWidgetLeftRight(viz, 10, Unit.PX, 10, Unit.PX);
viz.addCloseHandler(new CloseHandler<RequestLogVisualization>()
{
public void onClose(CloseEvent<RequestLogVisualization> event)
{
root.remove(viz);
}