private JLayeredPane getLayeredPane() {
    JLayeredPane layeredPane;
    final Window window = WindowManager.getInstance().suggestParentWindow(myProject);

    if (window instanceof JFrame) {
      layeredPane = ((JFrame)window).getLayeredPane();
    }
    else if (window instanceof JDialog) {
      layeredPane = ((JDialog)window).getLayeredPane();
    }
    else if (window instanceof JWindow) {
      layeredPane = ((JWindow)window).getLayeredPane();
    }
    else {
      throw new IllegalStateException("cannot find parent window: project=" + myProject +
                                      (myProject != null ? "; open=" + myProject.isOpen() : "") +
                                      "; window=" + window);
    }
    return layeredPane;
  }
private JLayeredPane getLayeredPane()