JDialog blocks parent window on Windows

Question

I have some problem with JDialog. I have Swing GUI created in NetBeans. GUI contains main frame with buttons, text fields, etc. When I click 'Next' button then JDialog (created aslo in NetBeans, Other Components section) is showing. Below are custom properties for this JDialog:

• modal = true;
• resizable = false;
• default close op = DISPOSE

The problem is that, on Windows XP (probably 7 too), when JDialog occurs then I can't minimalize application by minimalize parent form. On Ubuntu it is working as expected, but on Windows doesn't.

I have look into http://docs.oracle.com/javase/tutorial/uiswing/misc/modality.html and this example is working on Ubuntu and Widows as well. So, I tried to create sample JDialog manually as in it demo. And again on Ubuntu is woking, on Windows is not.

COuld someone have any idea? I have not any already.

SAmple DEMO, working on Ubuntu, not working on Windows XP:

package javaapplication5;

public class TWs extends javax.swing.JFrame {

    /**
     * Creates new form TWs
     */
    public TWs() {
        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() {

        jDialog1 = new javax.swing.JDialog();
        jLabel2 = new javax.swing.JLabel();
        jButton1 = new javax.swing.JButton();

        jDialog1.setModalityType(java.awt.Dialog.ModalityType.APPLICATION_MODAL);
        jDialog1.setResizable(false);

        jLabel2.setText("Sample Dialog");

        javax.swing.GroupLayout jDialog1Layout = new javax.swing.GroupLayout(jDialog1.getContentPane());
        jDialog1.getContentPane().setLayout(jDialog1Layout);
        jDialog1Layout.setHorizontalGroup(
            jDialog1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, jDialog1Layout.createSequentialGroup()
                .addContainerGap(212, Short.MAX_VALUE)
                .addComponent(jLabel2)
                .addGap(205, 205, 205))
        );
        jDialog1Layout.setVerticalGroup(
            jDialog1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(jDialog1Layout.createSequentialGroup()
                .addGap(122, 122, 122)
                .addComponent(jLabel2)
                .addContainerGap(160, Short.MAX_VALUE))
        );

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

        jButton1.setText("Show dialog");
        jButton1.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton1ActionPerformed(evt);
            }
        });

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGap(136, 136, 136)
                .addComponent(jButton1)
                .addContainerGap(164, Short.MAX_VALUE))
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGap(57, 57, 57)
                .addComponent(jButton1)
                .addContainerGap(213, Short.MAX_VALUE))
        );

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

    private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                                         
        jDialog1.setSize(200,200);
        jDialog1.setVisible(true);
    }                                        

    /**
     * @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(TWs.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(TWs.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(TWs.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(TWs.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 TWs().setVisible(true);
            }
        });
    }

    // Variables declaration - do not modify                     
    private javax.swing.JButton jButton1;
    private javax.swing.JDialog jDialog1;
    private javax.swing.JLabel jLabel2;
    // End of variables declaration                   
}

Answer 1

Please try the below comments

you just use this constructor JDialog(Parent, Title, model)

jDialog1 = new javax.swing.JDialog(this, "Test", false); 

and remove the line which sets modalityType .

jDialog1.setModalityType(java.awt.Dialog.ModalityType.APPLICATION_MODAL);

I hope it'll help.

(Please note that when you minimize tha JFrame the child JDialog will also get minimized)

Answer 2

The issue here is your expectations of how a modal dialogue should work, not the implementation that Swing uses.

The described behaviour on the different operating systems is correct. On the Windows OS, when a form is shown as modal it should completely disable the parent window and it's children, preventing any interaction with any of their controls. You can see this behaviour in Notepad in both the open dialogue box and the "are you sure" exit dialogue box.