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JComboBox Dropdown Menu Not Obeying AlwaysOnTop

I have an always-on-top window that I want to remain above all other windows. Using setAlwaysOnTop(true) seems to work for most purposes, but fails when it comes to JComboBox dropdown menus. Is there any way to prevent this from happening? Attached below is a SSCCE and picture of the undesired functionality.
EDIT: Not sure if the behavior is OS-dependent, but I'm noticing the issue on Windows 7 using Java 7. On top is supported on this OS.
EDIT 2: Seems that JPopupMenu has an override on alwaysOnTop() to return true. This is the source of the problem, since on-top components do not have a defined order in how they appear on top of each other (OS-dependent). Worse still, the method is package private. Quite problematic...
Undesired Behavior:
SSCCE:
import java.awt.BorderLayout;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JDialog;
import javax.swing.JTextField;
public class OnTopTest
{
public static void main( String[] args )
{
new OnTopTest();
}
public OnTopTest()
{
JDialog onTop = new OnTopWindow();
JDialog other = new OtherWindow();
System.out.println("IS ON TOP SUPPORTED? " + onTop.isAlwaysOnTopSupported());
other.setVisible( true );
onTop.setVisible( true );
}
private class OnTopWindow extends JDialog
{
public OnTopWindow()
{
setLayout( new BorderLayout() );
JButton button = new JButton("Button");
add( button, BorderLayout.CENTER );
setSize( 100, 100 );
setAlwaysOnTop( true );
}
}
private class OtherWindow extends JDialog
{
public OtherWindow()
{
setLayout( new BorderLayout() );
JTextField textField = new JTextField("Text");
add( textField, BorderLayout.NORTH);
JButton button = new JButton("Button");
add( button, BorderLayout.CENTER );
JComboBox comboBox = new JComboBox( new Object[] {"Item1", "Item2", "Item3"} );
add( comboBox, BorderLayout.SOUTH );
setSize( 200, 200 );
}
}
}

I'm pretty sure this is handled by the Operating System and that Java cannot force the dropdown to not overlap the other window, as searching for this without specifying Java reported the same behaviour in many different languages.
You can test with a JMenu to confirm, but I'm sure it will also happen as menus and some other controls (like dropdowns) will (by necessity) show above any other window.

Using an Example from Deitel's Java Book Not Working

// Fig. 14.6: LabelFrame.java
// Demonstrating the JLabel class.
import java.awt.FlowLayout; // specifies how components are arranged
import javax.swing.JFrame; // provides basic window features
import javax.swing.JLabel; // displays text and images
import javax.swing.SwingConstants; // common constants used with Swing
import javax.swing.Icon; // interface used to manipulate images
import javax.swing.ImageIcon; // loads images
public class LabelFrame extends JFrame
{
private JLabel label1; // JLabel with just text
private JLabel label2; // JLabel constructed with text and icon
private JLabel label3; // JLabel with added text and icon
// LabelFrame constructor adds JLabels to JFrame
public LabelFrame(){
{super( "Testing JLabel" );
setLayout( new FlowLayout() );
// JLabel constructor with a string argument
label1 = new JLabel( "Label with text" );
label1.setToolTipText( "This is label1" );
add( label1 );
//JLabel constructor with string, Icon and alignment arguments
Icon bug = new ImageIcon( getClass().getResource( "bug1.png" ) );
label2 = new JLabel( "Label with text and icon", bug,
SwingConstants.LEFT );
label2.setToolTipText( "This is label2" );
add( label2 );
label3 = new JLabel(); // JLabel constructor no arguments
label3.setText( "Label with icon and text at bottom" );
label3.setIcon( bug ); // add icon to JLabel
label3.setHorizontalTextPosition( SwingConstants.CENTER );
label3.setVerticalTextPosition( SwingConstants.BOTTOM );
label3.setToolTipText( "This is label3" );
add( label3 );
}
}
That was class one.
import javax.swing.JFrame;
public class LabelTest
{
public static void main( String[] args )
{
LabelFrame labelFrame = new LabelFrame(); // create LabelFrame
labelFrame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
labelFrame.setSize( 260, 180 ); // set frame size
labelFrame.setVisible( true ); // display frame
} // end main
}
This is class two.
I noticed that with the one untyped (LabelFrame) class did not have a type, but I copied from Deitel's Java book. I assumed we was correct, but so far this is not running because of that little piece of code. I am wondering if it could be an issue with the Java version, since mine is the latest, and the book is from 2012. If you could enlighten me on why this code won't run in Eclipse, that would be greatly appreciated. In addition, the add did not work. Thanks.

OK.. it seems the problem is that the code would not even compile cleanly. This was largely due to the lack of logical indentation leading to incorrectly placed brackets.
This code compile, but fails (here) at run-time due to the missing image.
import java.awt.FlowLayout; // specifies how components are arranged
import javax.swing.JFrame; // provides basic window features
import javax.swing.JLabel; // displays text and images
import javax.swing.SwingConstants; // common constants used with Swing
import javax.swing.Icon; // interface used to manipulate images
import javax.swing.ImageIcon; // loads images
public class LabelFrame extends JFrame
{
private JLabel label1; // JLabel with just text
private JLabel label2; // JLabel constructed with text and icon
private JLabel label3; // JLabel with added text and icon
// LabelFrame constructor adds JLabels to JFrame
public LabelFrame() {
super( "Testing JLabel" );
setLayout( new FlowLayout() );
// JLabel constructor with a string argument
label1 = new JLabel( "Label with text" );
label1.setToolTipText( "This is label1" );
add( label1 );
//JLabel constructor with string, Icon and alignment arguments
Icon bug = new ImageIcon( getClass().getResource( "bug1.png" ) );
label2 = new JLabel( "Label with text and icon", bug,
SwingConstants.LEFT );
label2.setToolTipText( "This is label2" );
add( label2 );
label3 = new JLabel(); // JLabel constructor no arguments
label3.setText( "Label with icon and text at bottom" );
label3.setIcon( bug ); // add icon to JLabel
label3.setHorizontalTextPosition( SwingConstants.CENTER );
label3.setVerticalTextPosition( SwingConstants.BOTTOM );
label3.setToolTipText( "This is label3" );
add( label3 );
}
public static void main( String[] args )
{
LabelFrame labelFrame = new LabelFrame(); // create LabelFrame
labelFrame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
labelFrame.setSize( 260, 180 ); // set frame size
labelFrame.setVisible( true ); // display frame
} // end main
}

The reason add is showing error is because you didn't "extend JFrame in the LabelFrame class,
It should be coded like this:
public class LabelFrame extends JFrame{
}
that should solve that problem, On the rest of your question, I'm having the same problem because the image is not there, It's null, If anyone can tell me how to get the image and use it, that would be greatly appreciated, Thanks!..

Copy and paste the picture in the package of your project and run the code.I hope it will work.
Another process:
Use
ImageIcon bug = new ImageIcon("java.png");//In the double quotes write the full path of the image.
instead of Icon bug = new ImageIcon( getClass().getResource( "bug1.png" ) );
I hope it will also work.

I faced the same problem. Here is the solution... just make a png image (using photoshop) and name it as bug1.png. Now just copy & paste the image in your project's src folder. Thats all.

How to Dynamically Add JButton to JPanel?

In NetBeans, I have used the GUI editor to make a JFrame and I've put a JPanel in the frame.
At the moment, I'm trying to make a new button in the panel when the class constructs.
This is the code I have, but I can't seem to get it to work.
(The first line makes the button, the other lines try to show it.)
this.jPanel2.add(new JButton("Test"),BorderLayout.NORTH);
this.jPanel2.validate();
this.jPanel2.revalidate();
this.jPanel2.repaint();
this.jPanel2.setVisible(true);
this.revalidate();
this.setVisible(true);
this.repaint();
I've been googling all night, but can't seem to get it to work.

Some times when you don't see a button it is a layout manager issue (as in you aren't setting the right properties for the layout manager). You can test this by disabling it:
this.jPanel2.setLayoutManager(null);
And setting bounds for the button (JButton.setBounds()).
If the above fixes your problem, then you need to look into the requirements set by the LayoutManager you are using (see also the answer by Robin).
All the calls to validate(), revalidate() and repaint() are not needed to do this.

Normally the add call is sufficient.
Note: a BorderLayout can only contain one component in each location. So if you add another component in the NORTH location, your button will not be visible.
Second note: by default a JPanel does not have a BorderLayout but a FlowLayout. Have you set a BorderLayout on that specific panel ? Otherwise the BorderLayout#NORTH constraint is incorrect
All the validate,revalidate,repaint calls can be removed
Edit
It seems some sort of validation is needed after all. I was under the impression that Swing should be smart enough to listen for the event when something is added to a Container, and update whatever is necessary (a bit similar to updating a TableModel updates the JTable based on events, without the need to call repaint or the likes on the JTable).
However, when trying this in an SSCCE, I came to the following code (different versions, only post the most elaborate version)
without the scroll-pane, the validate calls seem to have no effect. I actually need to call pack again to make the new labels visible (not included in the SSCCE, but removing the scrollpane from the code is trivial)
with the scroll-pane, the validate call has an effect
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class AddLabelsAtRuntime {
private int fLabelCounter = 0;
private JPanel fLabelPanel;
private final JFrame fTestFrame;
public AddLabelsAtRuntime() {
fLabelPanel = new JPanel( );
BoxLayout boxLayout = new BoxLayout( fLabelPanel, BoxLayout.PAGE_AXIS );
fLabelPanel.setLayout( boxLayout );
fTestFrame = new JFrame( "Dynamically add labels" );
}
private JFrame createUI(){
Container contentPane = fTestFrame.getContentPane();
contentPane.setLayout( new BorderLayout() );
JScrollPane scrollPane = new JScrollPane( fLabelPanel );
scrollPane.setPreferredSize( new Dimension( 200, 200 ) );
contentPane.add( scrollPane, BorderLayout.CENTER );
contentPane.add( createButtonPanel(), BorderLayout.SOUTH );
fTestFrame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
fTestFrame.pack();
return fTestFrame;
}
private void addLabel(){
fLabelPanel.add( new JLabel( "Label " + ++fLabelCounter ) );
}
private JPanel createButtonPanel(){
JPanel buttonPanel = new JPanel( );
BoxLayout boxLayout = new BoxLayout( buttonPanel, BoxLayout.LINE_AXIS );
buttonPanel.setLayout( boxLayout );
JButton validateButton = new JButton( "Add + validate" );
validateButton.addActionListener( new ActionListener() {
#Override
public void actionPerformed( ActionEvent e ) {
addLabel();
fLabelPanel.validate();
fTestFrame.validate();
}
} );
buttonPanel.add( validateButton );
JButton noValidateButton = new JButton( "Add" );
noValidateButton.addActionListener( new ActionListener() {
#Override
public void actionPerformed( ActionEvent e ) {
addLabel();
}
} );
buttonPanel.add( noValidateButton );
JButton packButton = new JButton( "Add + pack" );
packButton.addActionListener( new ActionListener() {
#Override
public void actionPerformed( ActionEvent e ) {
addLabel();
fTestFrame.pack();
}
} );
buttonPanel.add( packButton );
return buttonPanel;
}
public static void main( String[] args ) {
EventQueue.invokeLater( new Runnable() {
#Override
public void run() {
AddLabelsAtRuntime addLabelsAtRuntime = new AddLabelsAtRuntime();
addLabelsAtRuntime.createUI().setVisible( true );
}
} );
}
}

Create Dynamic JButton with Image and ActionListener - Java Swing
Create JButton dynamically with Image and the ActionListener . You will be able to change the button height , width horizontal gap and vertical gap in one place.
you can find more details from here

adding JLayeredPane to JPanel

I am trying to add a JLayeredPane to a JPanel and then add an image (JLabel icon) and a button to the JLayeredPane, but neither show up. I've tested the image without the button and the layeredpane so I know that works. Here is some of the code I am using. Is there something I am missing or doing wrong?
public class MyClass extends JPanel
{
private JLayeredPane layeredPane;
private JLabel imageContainer = new JLabel();
private JButton info = new JButton("i");
MyClass(ImageIcon image)
{
super();
this.imageContainer.setIcon(image);
this.layeredPane = new JLayeredPane();
layeredPane.setPreferredSize(new Dimension(300, 300));
layeredPane.add(imageContainer, new Integer(50));
layeredPane.add(info, new Integer(100));
this.add(layeredPane);
}
}

From the tutorial
By default a layered pane has no layout manager. This means that you typically have to write the code that positions and sizes the components you put in a layered pane.
See the changes to your code:
import java.awt.*;
import javax.swing.*;
public class MyClass extends JPanel {
private JLayeredPane layeredPane;
private JLabel imageContainer = new JLabel();
private JButton info = new JButton("i");
MyClass(ImageIcon image) {
super();
this.imageContainer.setIcon(image);
this.layeredPane = new JLayeredPane();
layeredPane.setPreferredSize(new Dimension(300, 300));
layeredPane.add(imageContainer, new Integer(50));
layeredPane.add(info, new Integer(100));
this.add(layeredPane);
// CHANGED CODE
// Manually set layout the components.
imageContainer.setBounds( 0, 0,
image.getIconWidth(),
image.getIconHeight() );
info.setBounds( 200, 00, 50, 40 );
}
public static void main( String [] args ) {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
frame.add( new MyClass( new ImageIcon("logo.png") ) );
frame.pack();
frame.setVisible( true );
}
}
Additional notes:
1) It is better ( in my opinion ) to put the opening brace in the same line. That's how most Java code looks like.
2) Avoid inheriting from JPanel ( or any other component ) if you don't are not really creating a subclass. You can use it directly without having to inherit ( unless you're indeed creating a new component.

JLayeredPane has a null layout manager by default, so in your example you'll need to set the location and size of the child components. You can set a layout manager on the JLayeredPane, but that will most likely negate the layered rendering I'm guessing you want, since you're using a layered pane.

Addin a JLabel in a frame?

I have created a JFrame, and now I want to add a JLabel and textfields in it. Please tell me how to do that. I have used the following code but its not working.
JFrame i_frame = new JFrame("Select Locations");
i_from = new JLabel("From");
i_frame.getContentPane().add(i_from);
i_frame.add(Box.createRigidArea(new Dimension(2,0)));
i_frame.setLocationRelativeTo(null);
i_frame.setSize(200,200);
i_frame.setVisible(true);
Problem is this code is showing frame window but it is not showing label in it. Please help.

That's your first question, later you'll ask:
How do I get the value from my text field
So, I suggest you to take a look at this tutorial
http://java.sun.com/docs/books/tutorial/uiswing/start/index.html
And ask us if you have questions from that tutorial. Using an IDE will simplify your life.
Here's a start anyway:
Code:
import javax.swing.*;
import java.awt.Color;
public class MyApp {
public static void main( String [] args ) {
JFrame frame = new JFrame();
frame.setBackground( new Color(0,0,0,64 ));
frame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
JPanel top = new JPanel();
top.add( new JLabel("What is your name"){{
setForeground(Color.white);
}});
top.add( new JTextField(10) );
frame.add( top );
frame.pack();
frame.setVisible( true );
}
}
EDIT
Dismiss this answer. It was posted when the question was rather ambiguous. I'm leaving it as CW for it may be helpful.
plus OSX frames with alpha background are too cool!

The main issue is the layout being used by the content pane (most likely JRootPane.RootLayout, A custom layout manager that is responsible for the layout of layeredPane, glassPane, and menuBar ) is not the best. This code should work;
JFrame i_frame = new JFrame("Select Locations");
JLabel i_from = new JLabel("From");
i_frame.getContentPane().setLayout(new FlowLayout());
i_frame.getContentPane().add(i_from);
i_frame.add(Box.createRigidArea(new Dimension(2,0)));
i_frame.setLocationRelativeTo(null);
i_frame.setSize(200,200);
i_frame.setVisible(true);
setting a different layout does the trick

The problem is that you are adding a second component (Box.createRigidArea) in the same layout position (BorderLayout.CENTER) as the Label.
JFrame.add() results in the same as JFrame.getContentPane().add()...
So the label is being replaced by the RigidArea.
Try this:
JFrame i_frame = new JFrame("Select Locations");
i_from = new JLabel("From");
i_frame.getContentPane().add(i_from);
// i_frame.add(Box.createRigidArea(new Dimension(2,0)));
i_frame.setLocationRelativeTo(null);
i_frame.setSize(200,200);
i_frame.setVisible(true);
to add more components, change the LayoutManager:
JFrame i_frame = new JFrame("Select Locations");
JLabel i_from = new JLabel("From");
Container pane = i_frame.getContentPane();
pane.setLayout(new BoxLayout(pane, BoxLayout.X_AXIS)); // any LayoutManager you need
pane.add(i_from);
pane.add(Box.createRigidArea(new Dimension(2,0))); // space after JLabel ?
i_frame.setSize(200,200); // better done before setLocationRelativeTo
i_frame.setLocationRelativeTo(null);
i_frame.setVisible(true);
Note: if you "just" want to add an empty border to your label, use a setBorder() instead of the RigidArea:
i_from.setBorder(BorderFactory.createEmptyBorder(2, 2, 2, 2));
[]]

For adding JLabel to JFrame see the line of code see here
public class JLabelExample extends JFrame {
JLabel jLabel;
public JLabelExample() {
jLabel = new JLabel();
jLabel.setText("tutorialData.com");
jLabel.setForeground(Color.BLUE);
this.add(jLabel);
}
public static void main(String a[]) {
JLabelExample labelExample = new JLabelExample();
labelExample.setSize(250, 200);
labelExample.setTitle("tutorialData.com");
labelExample.setVisible(true);
}
}
Please refer more on JFrame