Name: rmT116609 Date: 11/05/2003


FULL PRODUCT VERSION :
java version "1.4.2"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.2-b28)
Java HotSpot(TM) Client VM (build 1.4.2-b28, mixed mode)

FULL OS VERSION :
Microsoft Windows XP [Version 5.1.2600]

A DESCRIPTION OF THE PROBLEM :
We have an application that displays many panels, each with it's own menu bar. When we display a panel we display the corresponding menu bar using Frame.setJMenuBar. The menu doesn't change on the second or any subsequent call to setJMenuBar.



STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
1. Create a JFrame which contains a button.
2. Create 2 different menubars, say A and B
3. Set the frames menu bar to A initially
4. Add an action to the button to set the frame's menubar to B
5. Compile and run.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Menu bar A should be displayed until the button is pushed. After the button is pushed, menubar B should be displayed.
ACTUAL -
Menubar A is always displayed, even after the button push. Strange behavior occurs when the frame is repainted, sometimes it will display the menu, sometimes it will display the button text.

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.awt.event.*;

import javax.swing.*;

public class MenuBarTest extends JFrame {

  // Menu A
  private JMenuBar menubarA = new JMenuBar();
    // A Menu
    private JMenu menu1 = new JMenu("MenuA");

     // Menu A
  private JMenuBar menubarB = new JMenuBar();
    // A Menu
    private JMenu menu2 = new JMenu("MenuB");

  // Actions
  private Action switchMenuAction = new AbstractAction("Switch Menus") {
    public void actionPerformed(ActionEvent e) {
      switchMenuAction_actionPerformed();
    }
  };

  // Buttons
  JButton switchMenuButton = new JButton(switchMenuAction);

  public static void main(String[] args) {
    MenuBarTest test = new MenuBarTest();
    test.setVisible(true);
  }

  public void switchMenuAction_actionPerformed() {
    this.setJMenuBar(menubarB);
// doesn't fix bug
// this.repaint();
// workaround for bug
// SwingUtilities.updateComponentTreeUI(this);
  }

  public MenuBarTest() {
    this.getContentPane().add(switchMenuButton);
    this.setJMenuBar(menubarA);

    menubarA.add(menu1);
    menubarB.add(menu2);

    pack();
  }
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
The only way to get the menu to display is to call SwingUtilities.updateComponentTreeUI(this) in the JFrame after setting the JMenuBar (see http://www.jguru.com/forums/view.jsp?EID=1100274).
(Incident Review ID: 191832)
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