setSize(new Dimension(800,600));
viewer = new VisualizationViewer( new DefaultVisualizationModel(new XMLPersistingLayout(
propName != null? new FRLayout(g):new KKLayout(g))), constructRenderer(g) );
viewer.setBackground(Color.WHITE);
final DefaultModalGraphMouse graphMouse = new XMLModalGraphMouse();
graphMouse.setMode(ModalGraphMouse.Mode.PICKING);
graphMouse.add(new PickingGraphMousePlugin());
viewer.setGraphMouse(graphMouse);
viewer.setPickSupport(new ShapePickSupport());
viewer.addMouseListener(this);
popupMenu = new JPopupMenu();
JMenuItem item = new JMenuItem("pick");item.addActionListener(new ActionListener(){