protected void initializeOverview() {
LightweightSystem lws = new LightweightSystem(overview);
RootEditPart rep = getGraphicalViewer().getRootEditPart();
if (rep instanceof ScalableRootEditPart) {
ScalableRootEditPart root = (ScalableRootEditPart) rep;
thumbnail = new ScrollableThumbnail((Viewport) root.getFigure());
thumbnail.setBorder(new MarginBorder(3));
thumbnail.setSource(root
.getLayer(LayerConstants.PRINTABLE_LAYERS));
lws.setContents(thumbnail);
disposeListener = new DisposeListener() {
public void widgetDisposed(DisposeEvent e) {