Question

I have an application that has a main GUI with a menubar, and another fullscreen frame, which makes some parts of the main GUI appear in fullscreen exclusive mode. When I am in fullscreen mode, I would like to bind a drop-down menu from the menu bar as jpopupmenu.

Swing provides the function getPopupMenu() in JMenu. This function seems to work fine at first glance. I can hover over the menuitems and move to and view the submenus. Hovering over the submenus does emphasize the submenus, hovering over a plain menuitem (or radiobuttonmenuitem or checkboxmenuitem) does not emphasize the item. However, I can’t actually click on a menuitem. The keyboard-shortcuts do actually work fine, though. The problem is essentially the same as presented on this forum (where the problem is not solved, though):

http://www.java-forums.org/new-java/16463-jmenu-jpopupmenu.html

If I add a JMenuItem after the menubar has been initialized and used/shown in the main GUI (thus when switching to the fullscreen frame), the menu-item is actually clickable. This menu-item is in turn also clickable in the menubar of the main GUI. Executing getPopupMenu() directly after initializing the jMenu does not change anything. Not using the fullscreen exclusive-mode does also not change anything about the problem.

Edit

It seems I left out some important information: I’m testing the app on Mac OSX and using:
System.setProperty("apple.laf.useScreenMenuBar", "true");

To make the menu bar use the native menubar. If I disable this, the popup-menu works as expected. This seems like a bug in the mac java API? Is their some way to overcome, this?

I apologize for forgetting mentioning this, I wasn’t aware this would influence anything (though it seems kind of obvious).

Answer 1

Okay, I’m probably missing something, but I hacked this together really quickly and have no issues

public class PopupFrame extends javax.swing.JFrame {

    /**
     * Creates new form PopupFrame
     */
    public PopupFrame() {
        initComponents();
    }

    /**
     * This method is called from within the constructor to initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is always
     * regenerated by the Form Editor.
     */
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">
    private void initComponents() {

        jMenuBar1 = new javax.swing.JMenuBar();
        mnuFile = new javax.swing.JMenu();
        jMenuItem1 = new javax.swing.JMenuItem();
        jMenuItem2 = new javax.swing.JMenuItem();
        jMenuItem3 = new javax.swing.JMenuItem();
        jMenuItem4 = new javax.swing.JMenuItem();
        jMenuItem5 = new javax.swing.JMenuItem();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
        addMouseListener(new java.awt.event.MouseAdapter() {
            public void mousePressed(java.awt.event.MouseEvent evt) {
                doMouseClicked(evt);
            }
            public void mouseReleased(java.awt.event.MouseEvent evt) {
                doMouseClicked(evt);
            }
            public void mouseClicked(java.awt.event.MouseEvent evt) {
                doMouseClicked(evt);
            }
        });

        mnuFile.setText("File");

        jMenuItem1.setText("New");
        jMenuItem1.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                doActionPerformed(evt);
            }
        });
        mnuFile.add(jMenuItem1);

        jMenuItem2.setText("Open");
        jMenuItem2.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                doActionPerformed(evt);
            }
        });
        mnuFile.add(jMenuItem2);

        jMenuItem3.setText("Save");
        jMenuItem3.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                doActionPerformed(evt);
            }
        });
        mnuFile.add(jMenuItem3);

        jMenuItem4.setText("Close");
        jMenuItem4.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                doActionPerformed(evt);
            }
        });
        mnuFile.add(jMenuItem4);

        jMenuItem5.setText("Exit");
        jMenuItem5.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                doActionPerformed(evt);
            }
        });
        mnuFile.add(jMenuItem5);

        jMenuBar1.add(mnuFile);

        setJMenuBar(jMenuBar1);

        org.jdesktop.layout.GroupLayout layout = new org.jdesktop.layout.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING)
            .add(0, 400, Short.MAX_VALUE)
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING)
            .add(0, 278, Short.MAX_VALUE)
        );

        pack();
    }// </editor-fold>

    private void doActionPerformed(java.awt.event.ActionEvent evt) {

        JMenuItem mi = (JMenuItem) evt.getSource();

        JOptionPane.showMessageDialog(this, "Clicked " + mi.getText());

    }

    private void doMouseClicked(java.awt.event.MouseEvent evt) {

        if (evt.isPopupTrigger()) {

            JPopupMenu popupMenu = mnuFile.getPopupMenu();
            popupMenu.show(this, evt.getX(), evt.getY());

        }

    }

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {
        /*
         * Set the Nimbus look and feel
         */
        //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
        /*
         * If Nimbus (introduced in Java SE 6) is not available, stay with the
         * default look and feel. For details see
         * http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
         */
        try {
            for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
                if ("Nimbus".equals(info.getName())) {
                    javax.swing.UIManager.setLookAndFeel(info.getClassName());
                    break;
                }
            }
        } catch (ClassNotFoundException ex) {
            java.util.logging.Logger.getLogger(PopupFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(PopupFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(PopupFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(PopupFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        }
        //</editor-fold>

        /*
         * Create and display the form
         */
        java.awt.EventQueue.invokeLater(new Runnable() {

            public void run() {
                new PopupFrame().setVisible(true);
            }
        });
    }
    // Variables declaration - do not modify
    private javax.swing.JMenuBar jMenuBar1;
    private javax.swing.JMenuItem jMenuItem1;
    private javax.swing.JMenuItem jMenuItem2;
    private javax.swing.JMenuItem jMenuItem3;
    private javax.swing.JMenuItem jMenuItem4;
    private javax.swing.JMenuItem jMenuItem5;
    private javax.swing.JMenu mnuFile;
    // End of variables declaration
}

I apologies, I had to put it together while my 3 month old had a nap, so it’s quick and ugly 😛

UPDATE

After some playing around, it would seem that when we invoke the popup ourselves, I was changing the popup’s parent reference (invoker) which meant that when the JMenu tried to show the popup, the context was all wrong.

I updated the doActionPerformed method to look like this:

JOptionPane.showMessageDialog(this, "Clicked " + mi.getText());
JPopupMenu popupMenu = mnuFile.getPopupMenu();
popupMenu.setInvoker(mnuFile);

Basically, resting the popup’s client reference.