Keep visible the JPopupMenu while clicking on CheckBox

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

Code

JMenuItem mi = new JMenuItem(" ");
mi.setLayout(new BorderLayout());
mi.add(new JCheckBox(title) {
  private transient MouseAdapter handler;
  @Override public void updateUI() {
    removeMouseListener(handler);
    removeMouseMotionListener(handler);
    super.updateUI();
    handler = new DispatchParentHandler();
    addMouseListener(handler);
    addMouseMotionListener(handler);
    setFocusable(false);
    setOpaque(false);
  }
});
popup.add(mi);

popup.add(new JCheckBoxMenuItem("keeping open #2") {
  @Override public void updateUI() {
    super.updateUI();
    setUI(new BasicCheckBoxMenuItemUI() {
      @Override protected void doClick(MenuSelectionManager msm) {
        //super.doClick(msm);
        System.out.println("MenuSelectionManager: doClick");
        menuItem.doClick(0);
      }
    });
  }
});

// https://bugs.openjdk.java.net/browse/JDK-8165234
// Provide a way to not close toggle menu items on mouse click on component level
// JDK 9
JMenuItem menuItem = new JMenuItem("JMenuItem");
menuItem.putClientProperty("CheckBoxMenuItem.doNotCloseOnMouseClick", true);

References

• swing - How to prevent JPopUpMenu disappearing when checking checkboxes in it? - Stack Overflow
• Keep visible the JPopupMenu while clicking on CheckBox(Japanese)
• [JDK-8165234] Provide a way to not close toggle menu items on mouse click on component level - Java Bug System