Swing/PopupMenuBlockLayer のバックアップ(No.14)

class DisableInputLayerUI<V extends Component> extends LayerUI<V> {
  private static final String CMD_REPAINT = "lock";
  private final MouseListener emptyMouseAdapter = new MouseAdapter() {
    /* do nothing listener */
  };
  private boolean isBlocking;

  public void setLocked(boolean flag) {
    firePropertyChange(CMD_REPAINT, isBlocking, flag);
    isBlocking = flag;
  }

  @Override public void installUI(JComponent c) {
    super.installUI(c);
    if (c instanceof JLayer) {
      JLayer<?> jlayer = (JLayer<?>) c;
      jlayer.getGlassPane().addMouseListener(emptyMouseAdapter);
      jlayer.setLayerEventMask(
          AWTEvent.MOUSE_EVENT_MASK
          | AWTEvent.MOUSE_MOTION_EVENT_MASK
          | AWTEvent.MOUSE_WHEEL_EVENT_MASK
          | AWTEvent.KEY_EVENT_MASK);
    }
  }

  @Override public void uninstallUI(JComponent c) {
    if (c instanceof JLayer) {
      JLayer<?> jlayer = (JLayer<?>) c;
      jlayer.setLayerEventMask(0);
      jlayer.getGlassPane().removeMouseListener(emptyMouseAdapter);
    }
    super.uninstallUI(c);
  }

  @Override public void eventDispatched(
      AWTEvent e, JLayer<? extends V> l) {
    if (isBlocking && e instanceof InputEvent) {
      ((InputEvent) e).consume();
    }
  }

  @Override public void applyPropertyChange(
      PropertyChangeEvent e, JLayer<? extends V> l) {
    if (CMD_REPAINT.equals(e.getPropertyName())) {
      l.getGlassPane().setVisible((Boolean) e.getNewValue());
    }
  }
}