Long pressing the JButton to get a JPopupMenu

• download example.jar
• download src.zip
• repository

Code

class PressAndHoldHandler extends AbstractAction implements MouseListener {
  public final JPopupMenu pop = new JPopupMenu();
  public final ButtonGroup bg = new ButtonGroup();
  private AbstractButton arrowButton;
  private final Timer holdTimer = new Timer(1000, new ActionListener() {
    @Override public void actionPerformed(ActionEvent e) {
      System.out.println("InitialDelay(1000)");
      if (arrowButton != null && arrowButton.getModel().isPressed()
          && holdTimer.isRunning()) {
        holdTimer.stop();
        pop.show(arrowButton, 0, arrowButton.getHeight());
        pop.requestFocusInWindow();
      }
    }
  });
  public PressAndHoldHandler() {
    super();
    holdTimer.setInitialDelay(1000);
    pop.setLayout(new GridLayout(0, 3, 5, 5));
    for (MenuContext m: makeMenuList()) {
      AbstractButton b = new JRadioButton(m.command);
      b.setActionCommand(m.command);
      b.setForeground(m.color);
      b.setBorder(BorderFactory.createEmptyBorder());
      b.addActionListener(new ActionListener() {
        @Override public void actionPerformed(ActionEvent e) {
          System.out.println(bg.getSelection().getActionCommand());
          pop.setVisible(false);
        }
      });
      pop.add(b);
      bg.add(b);
    }
  }
  private List makeMenuList() {
    return Arrays.asList(
      new MenuContext("BLACK",   Color.BLACK),
      new MenuContext("BLUE",  Color.BLUE),
      new MenuContext("CYAN",  Color.CYAN),
      new MenuContext("GREEN",   Color.GREEN),
      new MenuContext("MAGENTA", Color.MAGENTA),
      new MenuContext("ORANGE",  Color.ORANGE),
      new MenuContext("PINK",  Color.PINK),
      new MenuContext("RED",   Color.RED),
      new MenuContext("YELLOW",  Color.YELLOW));
  }
  @Override public void actionPerformed(ActionEvent e) {
    System.out.println("actionPerformed");
    if (holdTimer.isRunning()) {
      ButtonModel model = bg.getSelection();
      if (model != null) {
        System.out.println(model.getActionCommand());
      }
      holdTimer.stop();
    }
  }
  @Override public void mousePressed(MouseEvent e) {
    System.out.println("mousePressed");
    Component c = e.getComponent();
    if (SwingUtilities.isLeftMouseButton(e) && c.isEnabled()) {
      arrowButton = (AbstractButton) c;
      holdTimer.start();
    }
  }
  @Override public void mouseReleased(MouseEvent e) {
    holdTimer.stop();
  }
  @Override public void mouseExited(MouseEvent e) {
    if (holdTimer.isRunning()) {
      holdTimer.stop();
    }
  }
  @Override public void mouseEntered(MouseEvent e) { /* not needed */ }
  @Override public void mouseClicked(MouseEvent e) { /* not needed */ }
}

References

• Long pressing the JButton to get a JPopupMenu(Japanese)