Menubar not added in a java split pane

Question

I have written a small test program which creates a split pane in which one of the pane's is a text area. I have added a meubar and menuitems to the pane but i donot see them in the gui that is created.

Could anyone pls point out what the wrong thing did i do over here in the below program:

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.JMenuBar;
import java.util.*;
import javax.swing.text.BadLocationException;
import java.awt.*;
import java.io.IOException;


//SplitPaneDemo itself is not a visible component.
public class SplitPaneDemo extends JFrame
                          implements ActionListener {

    private JTextArea ta;
    private JMenuBar menuB;
        private JMenu dbM;
        private JMenuItem cnadb,bsmdb,cdmdb;
     private JLabel picture;


    private JSplitPane splitPane;
    public SplitPaneDemo() {

        ta = new JTextArea(); //textarea
        ta.setLineWrap(true);
            ta.setWrapStyleWord(true);
            ta.addKeyListener(new KeyAdapter()
        {
                 public void keyPressed(KeyEvent ke )
                 {

                 int code = ke.getKeyCode();
                 int modifiers = ke.getModifiers();
                 if(code == KeyEvent.VK_ENTER && modifiers == KeyEvent.CTRL_MASK)
                 {
                  System.out.println("cmd in table:");
           }
                }
                });

        JScrollPane taPane = new JScrollPane(ta);
        picture = new JLabel();
        picture.setFont(picture.getFont().deriveFont(Font.ITALIC));
        picture.setHorizontalAlignment(JLabel.CENTER);

        JScrollPane pictureScrollPane = new JScrollPane(picture);

        splitPane = new JSplitPane(JSplitPane.VERTICAL_SPLIT,
                                   taPane, pictureScrollPane);
        splitPane.setOneTouchExpandable(true);
        splitPane.setDividerLocation(450);

        //Provide minimum sizes for the two components in the split pane.
        Dimension minimumSize = new Dimension(100, 100);
        taPane.setMinimumSize(minimumSize);
        pictureScrollPane.setMinimumSize(minimumSize);

        //Provide a preferred size for the split pane.
        splitPane.setPreferredSize(new Dimension(900, 900));

              menuB = new JMenuBar(); //menubar
        dbM = new JMenu("DB"); //file menu
            cnadb = new JMenuItem("CNA");
            bsmdb = new JMenuItem("BSM");
            cdmdb = new JMenuItem("CDM");
            setJMenuBar(menuB);
            menuB.add(dbM);
            dbM.add(cnadb);
            dbM.add(bsmdb);
            dbM.add(cdmdb);
            cnadb.addActionListener(this);
            bsmdb.addActionListener(this);
            cdmdb.addActionListener(this);
            setVisible(true);
    }
        public void actionPerformed(ActionEvent e) 
        {
    }
    public void valueChanged(ListSelectionEvent e) {
    }

    public JSplitPane getSplitPane() {
        return splitPane;
    }


    private static void createAndShowGUI() {

        //Create and set up the window.
        JFrame frame = new JFrame("SplitPaneDemo");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        SplitPaneDemo splitPaneDemo = new SplitPaneDemo();
        frame.getContentPane().add(splitPaneDemo.getSplitPane());

        //Display the window.
        frame.pack();
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        //Schedule a job for the event-dispatching thread:
        //creating and showing this application's GUI.
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGUI();
            }
        });
    }


}

Answer 1

You add the JMenuBar in your SplitPaneDemo class, but when you actually call createAndShowGUI, you make a new JFrame and only add the SplitPane to it with the call to getSplitPane. This new frame has no knowledge of the menu bar.

If you are extending JFrame in SplitPaneDemo, why not use that to make the frame for your gui?