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JPanel not visible in JScrollPane

I have a JPanel which dynamically allocates buttons in a vertical layout. The problem is when I place this panel inside JScrollPane, the scrollPane appears vertically above my buttons. I'm not sure why this is happening. Here's the code:
public static void GUI ()
{
JFrame frame = new JFrame(GAME_TITLE);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setPreferredSize(new Dimension(400,600));
frame.setLayout(new GridLayout(0,1));
Menu theMenu = new Menu();
theMenu.setLayout(new GridLayout(mSize,0));
theMenu.setOpaque(true);
JScrollPane scroll = new JScrollPane(theMenu,JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
frame.add(scroll);
theMenu.createGameButtons(frame);
frame.pack();
frame.setVisible(true);
}
I've tried quite a few things with no success. Also, I'm attaching a link to a screen shot

Christian Hujer answered the question with:
The bug is in the code that is not visible. The bug is in the method createGameButtons. There, the buttons are created and added to the frame instead of adding them to the Menu itself (which I guess is a subclass of JPanel)

How to add a ScrollBar at the bottom of the JPanel when using GridLayout?

Hello i wanted to know how to add a ScrollBar at the bottom of a JPanel if i use GridLayout in my desktop app, as far as i know GridLayout only accept as parameter quantity of colums, rows and the horizontal and vertical gap. So how can i add a scroll bar and use it to see the information that's in the JPanel?

Put the JPanel with GridLayout into a JScrollPane. E.G. as seen with the two column GridLayout that displays the labels added to the nested layout example.

If you want the JSrollBar to scroll the JPanel with the gridlayout, then put the grid layout into a scrollpane (remember to extend the scrollable interface)
Read this page of the tutorial to learn how to.
IF you want to use the events from the JScrollBar to change the visible area of your panel then put the panel inside another panel with a JScrollbar on the bottom.
This is an example with a green panel and a scrollbar at the bottom
public class Window extends JFrame {
public Window() {
setPreferredSize(new Dimension(500, 500));
setMinimumSize(new Dimension(500, 500));
setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
JPanel panel = new JPanel();
panel.setPreferredSize(new Dimension(100, 100));
panel.setBackground(Color.GREEN);
getContentPane().add(panel, BorderLayout.CENTER);
JScrollBar scrollBar = new JScrollBar(JScrollBar.HORIZONTAL);
scrollBar.setMinimum(0);
scrollBar.setMaximum(100);
scrollBar.setBlockIncrement(30);
scrollBar.addAdjustmentListener(new AdjustmentListener() {
#Override
public void adjustmentValueChanged(AdjustmentEvent e) {
System.out.println("Adjustment changed");
}
});
getContentPane().add(scrollBar, BorderLayout.SOUTH);
setVisible(true);
}
public static void main(String[] args) {
new Window();
}
}

Any other way to add scrollbar to JPanel other than JscrollPane

I have developed a desktop application. Now in that app I want to add panel with a scrollbar. I am trying using JScrollPane, but its not working.
JPanel paraJPanel = new JPanel();
JScrollPane SP_para_list = new JScrollPane(paraJPanel);
add(SP_para_list).setBounds(10,30,250,350);
This way I am adding scrollbars to panel. But it shows only empty panel with borders. It is not showing components in the panel. Although I have added several labels in it. Is it correct? Is there any other way to add scroll bar to panel.
Thanks in advance

You need to set the PreferredSize for the panel, to make the scrollbar show up, like below.
even you do not set a layout, the panel already has a default layout set.
public static void main(String[] args)
{
JFrame frame = new JFrame();
JPanel panel = new JPanel()
{
#Override
public Dimension getPreferredSize() {
return new Dimension(800, 1000);
}
};
panel.add(new JLabel("Test1"));
panel.add(new JLabel("Test2"));
frame.getContentPane().add(new JScrollPane(panel), BorderLayout.CENTER);
frame.setSize(600, 800);
frame.setVisible(true);
}

Java JPanel inside JScrollPane?

I have a JFrame, in this JFrame I have a JPanel that I draw on, this Panel can be any size and so I placed it into a JScrollpane to let me scroll when the panel is larger than the window screen size.
Unfortunately does not work as I expected:
Making the JFrame window smaller than the JPanel size does not show scroll bars
The JScrollPane size now seems locked to the size of the JPanel I have added to it, where as before it resized to the bounds of it's JFrame window (it still kinda does this but only vertically now?!)
The JPanel seems to assume the size of the JScrollpane regardless of what I set for preferred size
I am sure I'm doing something stupid, if someone could point out what I would be most grateful!
JPanel imageCanvas = new JPanel(); // 'Canvas' to draw on
JScrollPane scrollPane = new JScrollPane();
// set size of 'canvas'
imageCanvas.setMinimumSize(new Dimension(100,100));
// Scroll pane smaller then the size of the canvas so we should get scroll bars right?
scrollPane.setMinimumSize(new Dimension(50,50));
// Add a border to 'canvas'
imageCanvas.setBorder(BorderFactory.createLineBorder(new java.awt.Color(0, 0, 0)));
scrollPane.setViewportView(imageCanvas);

setPreferredSize() is the trick, setMinimumSize() and even setSize() on the component will be ignored by JScrollPane. Here's a working example using a red border.
import java.awt.*;
import javax.swing.*;
public class Scroller extends JFrame {
public Scroller() throws HeadlessException {
final JPanel panel = new JPanel();
panel.setBorder(BorderFactory.createLineBorder(Color.red));
panel.setPreferredSize(new Dimension(800, 600));
final JScrollPane scroll = new JScrollPane(panel);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLayout(new BorderLayout());
add(scroll, BorderLayout.CENTER);
setSize(300, 300);
setVisible(true);
}
public static void main(final String[] args) throws Exception {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new Scroller().setVisible(true);
}
});
}
}

// suggest a size of 'canvas'
_ImageCanvas.setPreferredSize(new Dimension(100,100));
// Scroll pane smaller then the size of the canvas so we should get scroll bars right?
_ScrollPane.setPreferredSize(new Dimension(50,50));
// ..later
_Frame.pack();

Set preferred size on the canvas.
Increase dimensions 100,100 is too small atleast on my computer.
You may want to use new GridLayout(1,1); for you JFrame if you want the scrollpane to expand when you expand the frame.

As far as I remember there are 2 options:
define the preferredSize of _ImageCanvas
create a subclass of JPanel and implement Scrollable: http://docs.oracle.com/javase/7/docs/api/javax/swing/Scrollable.html
For more details, see the Javadoc:
http://docs.oracle.com/javase/7/docs/api/javax/swing/JScrollPane.html

Check out the Scrollable interface, this may help with the sizing issues.
These two method maybe helpful:
boolean getScrollableTracksViewportWidth();
boolean getScrollableTracksViewportHeight();

Swing: Showing a transparent Panel hovering over another Panel

I want to show a textArea showing some text (will show log lines) , and have an animated gif hoovering above it. I tried the solution described here , but all I get is a grey screen. Hints?
public class TestLayeredPanes {
private JFrame frame = new JFrame();
private JLayeredPane lpane = new JLayeredPane();
public TestLayeredPanes() {
frame.setPreferredSize(new Dimension(600, 400));
frame.setLayout(new BorderLayout());
frame.add(lpane, BorderLayout.CENTER);
//Build the animated icon
JLabel buildingIcon = new JLabel();
buildingIcon.setIcon(new ImageIcon(this.getClass().getResource(
"/com/ct/tasks/cmviewer/gui/progress_bar.gif")));
JPanel iconPanel = new JPanel();
iconPanel.add(buildingIcon);
//Build the textArea
JTextArea textLog = new JTextArea("Say something");
JPanel textPanel = new JPanel();
textPanel.add(new JScrollPane(textLog));
//Add the panels to the layered pane
lpane.add(textPanel, 0);
lpane.add(iconPanel, 1);
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
new TestLayeredPanes();
}
}

Try putting your animated GIF on the glass pane of your root pane:
http://download.oracle.com/javase/tutorial/uiswing/components/rootpane.html

JXLayer make easier to do that. Look at JXLayer samples.
You also can take a look at code of XSwingX

Since you started with a working example, why did you remove lines of code from the example you copied?
Layered panes don't use a layout manager therefore the size of your components are (0, 0), so there is nothing to display. The setBounds(...) method in the example are there for a reason.