public static void main(String[] argv) { JFrame dlg = new JFrame(); dlg.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); UndoDemo demo = new UndoDemo(); dlg.getContentPane().add("Center", demo); dlg.getContentPane().add("North", demo.createToolBar()); dlg.pack(); dlg.setVisible(true); }
public void redo() { instance.drawing.add(this); instance.repaint(); }
public void undo() { instance.drawing.remove(this); instance.repaint(); }