protected void installKeyboardActions() {
    InputMap input = peer
        .getInputMap(JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT);
    input.put(KeyStroke.getKeyStroke(KeyEvent.VK_C, InputEvent.ALT_MASK),
        POPUP_KEY);
    input.put(KeyStroke.getKeyStroke(KeyEvent.VK_PAGE_DOWN, 0), POPUP_KEY);

    peer.getActionMap().put(POPUP_KEY, new AbstractAction() {

      @Override
      public void actionPerformed(ActionEvent e) {
        showPopup(true);
      }
    });

  }
protected void installKeyboardActions()