static void subscribeTo(NavBarPanel panel) {
    if (panel.getClientProperty(LISTENER) != null) {
      unsubscribeFrom(panel);
    }

    final NavBarListener listener = new NavBarListener(panel);
    final Project project = panel.getProject();
    panel.putClientProperty(LISTENER, listener);
    KeyboardFocusManager.getCurrentKeyboardFocusManager().addPropertyChangeListener(listener);
    FileStatusManager.getInstance(project).addFileStatusListener(listener);
    PsiManager.getInstance(project).addPsiTreeChangeListener(listener);
    WolfTheProblemSolver.getInstance(project).addProblemListener(listener);
    ActionManager.getInstance().addAnActionListener(listener);

    final MessageBusConnection connection = project.getMessageBus().connect();
    connection.subscribe(ProjectTopics.PROJECT_ROOTS, listener);
    connection.subscribe(NavBarModelListener.NAV_BAR, listener);
    connection.subscribe(FileEditorManagerListener.FILE_EDITOR_MANAGER, listener);
    panel.putClientProperty(BUS, connection);
    panel.addKeyListener(listener);

    if (panel.isInFloatingMode()) {
      final Window window = SwingUtilities.windowForComponent(panel);
      if (window != null) {
        window.addWindowFocusListener(listener);
      }
    }
  }
 static void unsubscribeFrom(NavBarPanel panel) {
   final NavBarListener listener = (NavBarListener) panel.getClientProperty(LISTENER);
   panel.putClientProperty(LISTENER, null);
   if (listener != null) {
     final Project project = panel.getProject();
     KeyboardFocusManager.getCurrentKeyboardFocusManager().removePropertyChangeListener(listener);
     FileStatusManager.getInstance(project).removeFileStatusListener(listener);
     PsiManager.getInstance(project).removePsiTreeChangeListener(listener);
     WolfTheProblemSolver.getInstance(project).removeProblemListener(listener);
     ActionManager.getInstance().removeAnActionListener(listener);
     final MessageBusConnection connection = (MessageBusConnection) panel.getClientProperty(BUS);
     panel.putClientProperty(BUS, null);
     if (connection != null) {
       connection.disconnect();
     }
   }
 }