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Menu bar not showing in JFrame

I've added a a custom JPane and a custom JMenuBar to my JFrame. The JPane shows up just fine, but not the JMenuBar. I've defined the frame and the menu bar in different classes
Here's the frame class:
public class pixelFrame { //This frame will hold the a pixelPane for art creation. This will also hold a menu bar, defined in another file.
pixelPane editingArea;
pixelMenuBar menuBar;
public pixelFrame()
{
EventQueue.invokeLater(new Runnable() { //create a new thread at runtime
#Override
public void run() { //when the program runs, do the following
JFrame frame = new JFrame("Pixel Art Creator"); //create a new JFrame (similar to a regular window), and give it the following title
editingArea = new pixelPane();
menuBar = new pixelMenuBar();
frame.add(editingArea); //add a pixelPane named editingArea to the JFrame
frame.setJMenuBar(menuBar); //adds a menu to the JFrame
frame.pack(); //make the window big enough to fit all components (in this case, editingArea)
frame.setLocationRelativeTo(null); //set window to the center of the screen
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); //Stop the thread and terminate the program.
frame.validate();
frame.setVisible(true); //You can see the window.
menuBar.setVisible(true);
}
});
}
public static void main(String[] args)
{
pixelPane.gridEnabled = true; //changing another variable from pixelPane just for testing.
new pixelFrame(); //create an instance of pixelFrame.
}
}
And here's the menu bar:
public class pixelMenuBar extends JMenuBar {
/**
*
*/
private static final long serialVersionUID = 1L;
JMenuBar menuBar;
JMenu file, tool;
JMenuItem save, load, changeColor;
JCheckBoxMenuItem gLines;
public pixelMenuBar() {
menuBar = new JMenuBar();
//creates a "File" menu in the menu bar
file= new JMenu("File");
file.setMnemonic(KeyEvent.VK_F);
menuBar.add(file); //add the menu to the menu bar
//creates a "Tools" menu in the menu bar
tool = new JMenu("Tools");
tool.setMnemonic(KeyEvent.VK_T);
menuBar.add(tool);
//Menu items that go under the File menu
save = new JMenuItem("Save File"); //save and export the image as an .svg file
save.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.CTRL_DOWN_MASK,KeyEvent.VK_S)); //a Ctrl+S hotkey. Handy dandy!
file.add(save);//adds the Save button to the File menu
load = new JMenuItem("Load File"); //load the file into BufferedImage, make it into a JLabel and add it to the panel.
load.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.CTRL_DOWN_MASK,KeyEvent.VK_L));//a Ctrl+L hotkey. Also handy dandy!
file.add(load);//adds the Load button to the File menu
//Menu items that will go under the Tools menu
gLines = new JCheckBoxMenuItem("Gridlines"); //creates a new checkbox for enabling grid lines. will toggle pixelPane.gridEnabled
gLines.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.CTRL_DOWN_MASK,KeyEvent.VK_G));
tool.add(gLines);//adds the gridlines tool to the Tools menu
tool.addSeparator(); //adds a separating line in the Tools menu. Organization.
changeColor = new JMenuItem("Change Color");//creates a new menu item that will let the user the color of the pixel. Uses a color picker
tool.add(changeColor);//adds Change Color to the Tools menu
}
}
Am I not adding something to the UI correctly? I double checked that I'm using addJMenuBar() and not addMenuBar().

First of all class names SHOULD start with an upper case character. Have you ever seen a class in the Java API that doesn't? Follow Java conventions. Learn by example.
public class pixelMenuBar extends JMenuBar
{
...
public pixelMenuBar()
{
menuBar = new JMenuBar();
Your class "is a " JMenuBar, but the first thing you do in the class is create a JMenuBar.
Don't create the JMenuBar!
Just add the menu items to the JMenuBar class itself:
//menuBar.add(file); //add the menu to the menu bar
add(file); //add the menu to the menu bar
In reality there is no need to even have a PixelMenuBar class, since you are not adding any new functionality to the JMenuBar. Just add a method to your main class like createMenuBar(...) that creates the JMenuBar and adds the JMenu/JMenuItem objects.

Creating a Frame with MenuBar - Size not recognized by pack(), menubar is being cutoff

for an exercise I need to have a frame consisting of 2 buttons, and, if you click one, some text displaying. I need to also add a menubar. This works fine, it shows in the frame, but only the first menu. As I already found out, the problem is that using the pack() method, only the buttons size is considered, not the size of the menubar. And because the buttons are smaller than the menubar, it gets cutoff.
import java.awt.*;
public class Example extends Frame{
private MenuBar menuBar;
private Menu program;
private Menu messageSettings;
private MenuItem itmClose;
private MenuItem
public Example() {
menuBar = new MenuBar();
program = new Menu("Programm");
messageSettings = new Menu("Nachrichtenverwaltung");
itmClose = new MenuItem("Schließen");
itmWelcome = new MenuItem("Willkommen");
setLayout(new BorderLayout());
menuBar.add(program);
menuBar.add(messageSettings);
program.add(itmClose);
messageSettings.add(itmWelcome);
setMenuBar(menuBar);
pack(); //this one doesn't show a window
//setSize(400,600); //this one shows a Window
setVisible(true);
}
public static void main(String args[]) {
Example wnd = new Example();
}
}
For this minimal example, I only showed the menubar, for me, this code now opens an empty window. If I uncomment the setSize, I see the whole menubar.
I would be very glad if someone could help me out and get this to work, using pack() or another method not using fixed values. I also have to use AWT for this course.

Without a Component that has a preferred size, your window's content pane is empty. As an example, I've added a small, colored Panel below. As an exercise, try removing the arbitrary size and adding a Component such as Label or Button; experiment with different layout managers on the Panel.
import java.awt.*;
public class Example extends Frame {
private MenuBar menuBar = new MenuBar();
private Menu program = new Menu("Program");
private Menu message = new Menu("Nachrichtenverwaltung");
private MenuItem itmClose = new MenuItem("Schließen");
private MenuItem itmWelcome = new MenuItem("Willkommen");
public Example() {
menuBar.add(program);
menuBar.add(message);
program.add(itmClose);
message.add(itmWelcome);
setMenuBar(menuBar);
Panel panel = new Panel(){
#Override
public Dimension getPreferredSize() {
return new Dimension(320, 240);
}
};
panel.setBackground(Color.cyan.darker());
add(panel);
pack();
setVisible(true);
}
public static void main(String args[]) {
Example wnd = new Example();
}
}
Note that the platform pictured above moves the MenuBar to a place expected by users.

I would recommend using Java Swing library instead of using the old Java AWT library, unless you have to.
EDIT for detail:
The Swing library is much more portable than the AWT library. This is because it is a purely Java based GUI as opposed to AWT which uses most of the OS based GUI features. So, in terms of the OS, the swing library is just putting some pixels on the screen.
I find that the swing library is easier to use than AWT, although you do still have to use AWT for Listeners. I feel that it would be better for you to have a look into the swing API, as it should make it easier for you to do what you are trying.

I have a JLabel that doesn't want to update

I've looked at other JLabel threads and though similar, a few just don't seem to apply to what I'm experiencing. First, I want to say I am a novice when it comes to Java. Next, I am trying to follow tutorials and demos at the docs.oracle.com site. Now, I can update the label when I type something into a JTextField and there is an ActionListener on that...
But I also have a Menu, and when I select a Menu Item, that Action does not want to update the label.
Questions -
How do I have action listeners on both JTextFields and JMenuItems? Are there two ActionEvent methods or do I use one method and somehow identify each type of action?
If I use the same basic code in the JTextField ActionEvent and JMenuItem ActionEvent, the JLabel updates correctly with the JTextField event but not JMenuItem event. They both use the messageField.setText property. Could the JMenuItem action be doing something to block the setText?
I can easily copy code in here, but it's pretty spaghetti-like at the moment, so if you want to see anything, let me know specifically and I'll post it.
I would appreciate any assistance that anyone would be able to provide.
---edit---
Wow!! Thanks for all of the comments and suggestions.
1 - I know it has to be my code. As I mentioned, I am really just cobbling stuff together from demos and tutorials, and trying to learn Java along the way. I've just never gotten the hang of object oriented....
2 - I do know the individual Listeners are working. I'm using System.out.println to validate, as well as inspecting those labels in debug mode to see they have indeed changed.
3 - I will look at the various links and code posted here and see if I can figure out what's wrong with my code.
Really, thanks again!
---edit---
Here is what I originally had in my createAndShowGUI method....
private static void createAndShowGUI()
{
JFrame frame = new JFrame("Create XML for Photo Gallery");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
CreateGalleryXML window = new CreateGalleryXML();
frame.setJMenuBar(window.createMenuBar());
frame.add(new CreateGalleryXML());
frame.pack();
frame.setVisible(true);
}

Seems like you yourself are doing something wrong, in your code. Without a proper SSCCE it's hard to say what thing you doing wrong, since it works perfectly, using same ActionListener for both JMenuItem and JTextField.
Here is a sample program to match with yours :
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class UpdateLabel
{
private JLabel label;
private String labelText;
private ActionListener action = new ActionListener()
{
public void actionPerformed(ActionEvent ae)
{
setLabelText((String) ae.getActionCommand());
label.setText(getLabelText());
}
};
private void setLabelText(String text)
{
labelText = text;
}
private String getLabelText()
{
return labelText;
}
private void createAndDisplayGUI()
{
final JFrame frame = new JFrame("Update Label");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.setLocationByPlatform(true);
JMenuBar menuBar = new JMenuBar();
JMenu programMenu = new JMenu("Program");
JMenuItem exitMenuItem = new JMenuItem("Exit");
exitMenuItem.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent ae)
{
frame.dispose();
}
});
JMenu labelMenu = new JMenu("Label");
JMenuItem updateMenuItem = new JMenuItem("Update Label");
updateMenuItem.setActionCommand("Updated by JMenuItem");
updateMenuItem.addActionListener(action);
programMenu.add(exitMenuItem);
labelMenu.add(updateMenuItem);
menuBar.add(programMenu);
menuBar.add(labelMenu);
frame.setJMenuBar(menuBar);
JPanel contentPane = new JPanel();
label = new JLabel("I am the LABEL which will be updated!!");
contentPane.add(label);
JTextField tfield = new JTextField(10);
tfield.setActionCommand("Updated by JTextField");
tfield.addActionListener(action);
frame.add(contentPane, BorderLayout.CENTER);
frame.add(tfield, BorderLayout.PAGE_END);
frame.pack();
frame.setVisible(true);
}
public static void main(String... args)
{
SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
new UpdateLabel().createAndDisplayGUI();
}
});
}
}
And here is the output in both the cases :
and
Do check out the main method, might be you had failed to put your code inside EDT - Event Dispatcher Thread, that can lead to such issues too. All updates on the Swing GUI, must be done on the Event Dispatcher Thread.
LATEST EDIT
It seems to me that CreateGalleryXML extends JPanel by the look of it. See at Line 3 of this below code taken from your update, here you are initializing a new Object of CreateGalleryXML inside, when you already had one Object window created at Line 1:
CreateGalleryXML window = new CreateGalleryXML();
frame.setJMenuBar(window.createMenuBar());
frame.add(new CreateGalleryXML());
So try to change the above thingy to this
CreateGalleryXML window = new CreateGalleryXML();
frame.setJMenuBar(window.createMenuBar());
frame.add(window);
and see what happens and Please do revert back again :-)

Use Action to encapsulate common functionality that must be shared by menus and related components. See this example that extends AbstractAction.

Pretty much everything you could need to know is in the Java tutorials. Down the bottom they have demo's on how to do both menu's and text fields. They include source code to look at as well.
There's not much more I can say that they don't say better, but in answer to your questions:
Both, you can have separate listener's on each component, or one that figures out what component is responsible for causing the action event. I would suggest you use separate ones for each thing.
Can't really say with out seeing the code, are you sure that the action on the JMenu is even firing? Does it print something to the console etc if you use System.out.println somewhere?

strange java window behaviour

I am trying to write a simple desktop application for managing accounts. I am in the beginning phase.
I am running it in my old computer and I sometimes get strange behavior.
Java Version
java version "1.6.0_05"
Java(TM) SE Runtime Environment (build 1.6.0_05-b13)
Java HotSpot(TM) Client VM (build 10.0-b19, mixed mode, sharing)
My computer configuration
Microsoft Windows XP SP2
Intel(R) Celeron(R) CPU 2.53GHz 1.96GHz 736MB of RAM
I get strange behaviour. When I compile my program and the jframe loads, i sometimes get menu and sometimes I don't get menu as shown in the figure. Also when I try to resize my jframe, jframe shows menu.
My code
import javax.swing.*;
import java.awt.event.*;
import java.awt.*;
import java.awt.AWTException;
public class Main {
public static void main(String[] args) {
new Login();
}
}
class Login extends JFrame{
private int height=450;
private int width=300;
private Container container;
private GridBagLayout layout;
private GridBagConstraints constraints;
JTextArea textArea1, textArea2;
public Login()
{
initWindow();
initMenu();
}
private void initWindow()
{
setVisible(true);
setSize(this.height, this.width);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Toolkit toolkit = Toolkit.getDefaultToolkit ();
Dimension dim = toolkit.getScreenSize();
setLocation((dim.width-this.width)/2, (dim.height-this.height)/2);
Image image = toolkit.createImage("account.gif");
setIconImage(image);
}
private void initMenu()
{
JMenuBar menuBar = new JMenuBar();
setJMenuBar(menuBar);
JMenu fileMenu = new JMenu("File");
JMenu helpMenu = new JMenu("Help");
menuBar.add(fileMenu);
menuBar.add(helpMenu);
JMenuItem configureAction = new JMenuItem("Configure");
JMenuItem exitAction = new JMenuItem("Exit");
fileMenu.add(configureAction);
fileMenu.add(exitAction);
JMenuItem helpAction = new JMenuItem("Help");
JMenuItem aboutAction = new JMenuItem("About");
helpMenu.add(helpAction);
helpMenu.add(aboutAction);
}
}
Window with no menu
Window with menu
Any suggestion to improve code with be highly appreciated.
Thank you

Note that you get this erratic behaviour (rather than a consistent fail or consistent success) because of what “events” are delivered. For instance if you mouse over where the menubar is, or change window sizes you will see bits being painted “properly” because the underlying graphics stack detected these events and marked the affected regions for update.
You can mark GUI components for update as well using repaint() and/or revalidate().
Note that the above doesn't explain why your code did not work, the reason for that is as explained by the first answer, that you made the window visible before it was realised.
A few other tips: it's good practice to ensure all GUI creation occurs on the AWT EventQueue, by using something like
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
// call code which creates the GUI in here
}
}
Or the SwingUtilities.invokeLater() version.
Additionally, it is a good idea to call pack() on the frame before making it visible, since this will make the Window size it components properly and validate them (and without such validation, scrollpanes for instance won't update the scrollbars properly).

Don't call setVisible(true) until the window is completely built, ie. do that statement as the last thing you do with the window.
Once the window is visible, any changes you make to the window must be done on the GUI thread.

How can I create a "Drop-Down" menu in a Java Swing toolbar?

I've created a drop-down menu on my Swing JToolBar. But it doesn't create behave the way I want. I'm aiming for it to work like Firefox's "Smart Bookmarks" button.
It disappears when the user selects a menu item: CORRECT!
It disappears when the user presses ESC: CORRECT!
It disappears when the user clicks somewhere in the main frame outside of the menu: CORRECT!
But it doesn't disappear when the user clicks a second time on the button that shows the drop-down menu: INCORRECT... :-(
My question is how can I add this behaviour, that it does disappear when the clicks on the button that shows the menu a second time.
Here's my current code, from Java 6 on the Mac:
import javax.swing.*;
import javax.swing.event.PopupMenuEvent;
import javax.swing.event.PopupMenuListener;
import java.awt.*;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
public class ScratchSpace {
public static void main(String[] arguments) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
JFrame frame = new JFrame("Toolbar with Popup Menu demo");
final JToolBar toolBar = new JToolBar();
toolBar.add(createMoreButton());
final JPanel panel = new JPanel(new BorderLayout());
panel.add(toolBar, BorderLayout.NORTH);
panel.setPreferredSize(new Dimension(600, 400));
frame.getContentPane().add(panel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
private static AbstractButton createMoreButton() {
final JToggleButton moreButton = new JToggleButton("More...");
moreButton.addItemListener(new ItemListener() {
public void itemStateChanged(ItemEvent e) {
if (e.getStateChange() == ItemEvent.SELECTED) {
createAndShowMenu((JComponent) e.getSource(), moreButton);
}
}
});
moreButton.setFocusable(false);
moreButton.setHorizontalTextPosition(SwingConstants.LEADING);
return moreButton;
}
private static void createAndShowMenu(final JComponent component, final AbstractButton moreButton) {
JPopupMenu menu = new JPopupMenu();
menu.add(new JMenuItem("Black"));
menu.add(new JMenuItem("Red"));
menu.addPopupMenuListener(new PopupMenuListener() {
public void popupMenuWillBecomeVisible(PopupMenuEvent e) {
}
public void popupMenuWillBecomeInvisible(PopupMenuEvent e) {
moreButton.setSelected(false);
}
public void popupMenuCanceled(PopupMenuEvent e) {
moreButton.setSelected(false);
}
});
menu.show(component, 0, component.getHeight());
}
}

Well, here is a potential solution that is not without it's drawbacks. Only you can decide if this is acceptable for your application. The issue is that the popup closing occurs before other mouse-handling events are fired so clicking on your More.. button again causes the popup to hide, thus resetting the buttons state to deselected BEFORE the button even gets told it was pressed.
The easy workaround is to add the following call within your main program:
UIManager.put("PopupMenu.consumeEventOnClose", Boolean.TRUE);
The result of this is that whenever a popup menu is closed because of a mouse-pressed event, that mouse event will be consumed at the time the menu is closed and won't be passed on to any other components under the mouse. If you can live with limitation, this is an easy solution.

What's happening is that when you click off the menu, it cancels the popup menu, so you deselect the button, but the next immediate event is clicking the button, and now its deselected so it shows the menu again.
I don't have the exact solution yet, but give me a little bit ...

I don't use Firefox so I don't know what the Smart Bookmarks button looks like, but maybe use a JMenu as the "button". You could try using the Border of a JButton to make it look more like a button.

Well, the listener on the button reacts only when it is pushed down, because you listen for ItemEvent.SELECTED events only. How about adding another if clause to listen for ItemEvent.DESELECTED events here:
moreButton.addItemListener(new ItemListener() {
public void itemStateChanged(ItemEvent e) {
if (e.getStateChange() == ItemEvent.SELECTED) {
createAndShowMenu((JComponent) e.getSource(), moreButton);
}
}
});
You could either store a reference to the menu somewhere, or you could make the menu itself add another listener to the button. The latter solution could be more straightforward, since you already seem to send a button reference to the menu.