Eclipse : Minimizing the RCP App to the system tray.

ApplicationWorkbenchWindowAdvisor of the RCP application can handle preWindowShellClose() and postWindowClose(). If you want the application to be stored to the system tray when closed, the preWindowClose event can be handled as below to add a system tray icon with Open and Exit actions which will open/exit the workbench.

 @Override
 public boolean preWindowShellClose() {
  final TrayItem item = new TrayItem(
    Display.getCurrent().getSystemTray(), SWT.NONE);
  final Image image = Activator.getImageDescriptor("icons/mail.ico")
    .createImage();
  item.setImage(image);
  item.setToolTipText("RCPMail - Tray Icon");
  getWindowConfigurer().getWindow().getShell().setVisible(false);
  item.addSelectionListener(new SelectionAdapter() {
   public void widgetDefaultSelected(SelectionEvent e) {
    Shell workbenchWindowShell = getWindowConfigurer().getWindow()
      .getShell();
    workbenchWindowShell.setVisible(true);
    workbenchWindowShell.setActive();
    workbenchWindowShell.setFocus();
    workbenchWindowShell.setMinimized(false);
    image.dispose();
    item.dispose();
   }
  });

  Shell workbenchWindowShell = getWindowConfigurer().getWindow()
    .getShell();
  // Create a Menu
  final Menu menu = new Menu(workbenchWindowShell, SWT.POP_UP);
  // Create the exit menu item.
  final MenuItem exit = new MenuItem(menu, SWT.PUSH);
  exit.setText("Exit");

  // Create the open menu item.
  final MenuItem open = new MenuItem(menu, SWT.PUSH);
  open.setText("Open");
  // make the workbench visible in the event handler for exit menu item.
  open.addListener(SWT.Selection, new Listener() {
   public void handleEvent(Event event) {
    // Do a workbench close in the event handler for exit menu item.
    exit.addListener(SWT.Selection, new Listener() {
     public void handleEvent(Event event) {
      image.dispose();
      item.dispose();
      open.dispose();
      exit.dispose();
      menu.dispose();
      getWindowConfigurer().getWorkbenchConfigurer().getWorkbench()
        .close();
     }
    });    Shell workbenchWindowShell = getWindowConfigurer().getWindow()
      .getShell();
    workbenchWindowShell.setVisible(true);
    workbenchWindowShell.setActive();
    workbenchWindowShell.setFocus();
    workbenchWindowShell.setMinimized(false);
    image.dispose();
    item.dispose();
    open.dispose();
    exit.dispose();
    menu.dispose();
   }
  });
  item.addListener(SWT.MenuDetect, new Listener() {
   public void handleEvent(Event event) {
    menu.setVisible(true);
   }
  });
  // Do a workbench close in the event handler for exit menu item.
  exit.addListener(SWT.Selection, new Listener() {
   public void handleEvent(Event event) {
    image.dispose();
    item.dispose();
    open.dispose();
    exit.dispose();
    menu.dispose();
    getWindowConfigurer().getWorkbenchConfigurer().getWorkbench()
      .close();
   }
  });
  return false;
 }