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Can't get absolute JLabel location

My JFrame uses a BorderLayout and it has a JLabel nested in several panels with different layout managers. I've tried several methods, however, cannot get the true position of where it sits in the frame.
I made a test UI and it seems like when other components are added the getX and getY parameters do not update. Other methods like getLocation do not provide a correct result either. Is there any way to obtain the exact location without manually calculating every possible offset from each component.
I am tracking the stated positions of the label (content) using a similar sized panel called content2 in the glass pane which I want to sit underneath content perfectly.
public class test {
private Dimension pSize = new Dimension(100,100);
private JFrame frame = new JFrame();
public static void main(String[] args) {
new test();
}
public test() {
//setup frame basics
frame.setPreferredSize(new Dimension(500,500));
frame.setLayout(new BorderLayout());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
// setup GUI
JMenuBar j = new JMenuBar();
JMenuItem a = new JMenuItem("lol");
j.add(a);
JPanel j2 = new JPanel();
//setup main panel
JPanel main = new JPanel();
main.setBackground(Color.DARK_GRAY);
//setup side panel
FlowLayout f1 = new FlowLayout(FlowLayout.LEADING);
f1.setHgap(10);
f1.setVgap(0);
JPanel side = new JPanel();
side.setLayout(new BorderLayout());
side.setBackground(Color.gray);
side.setPreferredSize(new Dimension(150,100));
//setup JLabel (the main focus)
JLabel content = new JLabel("a");
content.setOpaque(true);
content.setBackground(Color.blue);
content.setPreferredSize(pSize);
// Setup the internal panels of side
JPanel top = new JPanel();//The panel where CONTENT is, the main focus
JPanel bot = new JPanel();
top.setBackground(Color.WHITE);
bot.setBackground(Color.orange);
top.setLayout(f1);
top.add(content);
side.add(top, BorderLayout.NORTH);
side.add(bot, BorderLayout.CENTER);
frame.add(main, BorderLayout.CENTER);
frame.add(side, BorderLayout.WEST);
frame.add(j2, BorderLayout.NORTH);
frame.setJMenuBar(j);
frame.pack();
frame.setVisible(true);
//Setting up the glass panel
JPanel pane = new JPanel();
pane.setLayout(null);
pane.setOpaque(false);
JPanel content2 = new JPanel();
content2.setBackground(Color.red);
content.revalidate();
int x = content.getX();
int y = content.getY();
// y = (int) content.getLocation().getY(); //returns a completely wrong location
//y = (int) content.getLocationOnScreen(); //returns a completely wrong location
/*
Point p = new Point();
p.setLocation(x, y);
p = SwingUtilities.convertPoint(content2, x, y, frame);
//SwingUtilities.convertPoint(content, p, frame);
y = (int) p.getY();
*
* Tried multiple SwingUtility converions to no avail
*
*/
// y = y +j.getHeight() + j2.getHeight(); // Manually calculating the Y off set works successfully but is too tedious for large project
y = y + content.getHeight();
content2.setBounds(x,y,100,100);
pane.add(content2);
frame.setGlassPane(pane);
frame.getGlassPane().setVisible(true);
frame.pack();
}
}
//frame.getContentPane().add(content);
//frame.add(content);
frame.setPreferredSize(new Dimension(500,500));
content.setBorder(BorderFactory.createEmptyBorder());
side.setLayout(new BorderLayout());
JPanel top = new JPanel();
JPanel bot = new JPanel();
top.setBackground(Color.WHITE);
bot.setBackground(Color.orange);
side.add(top, BorderLayout.NORTH);
top.setLayout(f1);
top.add(content);
side.add(bot, BorderLayout.CENTER);
frame.add(main, BorderLayout.CENTER);
frame.add(j2, BorderLayout.NORTH);
frame.add(side, BorderLayout.WEST);
frame.pack();
frame.setVisible(true);
JPanel pane = new JPanel();
pane.setLayout(null);
pane.setOpaque(false);
JPanel content2 = new JPanel();
content2.setBackground(Color.red);
content.revalidate();
int x = content.getX();
int y = content.getY();
// y = y +j.getHeight() + j2.getHeight();
y = y + content.getHeight();
content2.setBounds(x,y,100,100);
pane.add(content2);
frame.setGlassPane(pane);
frame.getGlassPane().setVisible(true);
frame.pack();
}
}

Conceptually you could make use of SwingUtilities.convertPoint or SwingUtilities.convertRectangle to convert between container contexts, for example...
import java.awt.Color;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GridBagLayout;
import java.awt.Rectangle;
import java.util.ArrayList;
import java.util.List;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.border.EmptyBorder;
public class Main {
public static void main(String[] args) {
new Main();
}
public Main() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
GlassPane glassPane = new GlassPane();
JFrame frame = new JFrame();
frame.setGlassPane(glassPane);
frame.add(new MainPane(glassPane));
glassPane.setVisible(true);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public interface Tracker {
public void addTrackable(Trackable trackable);
public void removeTrackable(Trackable trackable);
}
public interface Trackable {
public JComponent[] getTrackedComponents();
}
public class MainPane extends JPanel {
private JLabel label = new JLabel("Catch me if you can");
public MainPane(Tracker tracker) {
setLayout(new GridBagLayout());
setBorder(new EmptyBorder(32, 32, 32, 32));
add(label);
tracker.addTrackable(new Trackable() {
#Override
public JComponent[] getTrackedComponents() {
return new JComponent[] { label };
}
});
}
}
public class GlassPane extends JPanel implements Tracker {
private List<Trackable> trackables = new ArrayList<>(8);
public GlassPane() {
setOpaque(false);
}
#Override
public void addTrackable(Trackable trackable) {
trackables.add(trackable);
revalidate();
repaint();
}
#Override
public void removeTrackable(Trackable trackable) {
trackables.remove(trackable);
revalidate();
repaint();
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
g2d.setColor(Color.RED);
for (Trackable trackable : trackables) {
for (JComponent component : trackable.getTrackedComponents()) {
Rectangle relativeBounds = SwingUtilities.convertRectangle(component.getParent(), component.getBounds(), this);
g2d.draw(relativeBounds);
}
}
g2d.dispose();
}
}
}
Well, that's pretty boring, it's one component inside one container, let's trying something a little more complicated...
import java.awt.Color;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GridBagLayout;
import java.awt.GridLayout;
import java.awt.Rectangle;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.border.CompoundBorder;
import javax.swing.border.EmptyBorder;
import javax.swing.border.LineBorder;
public class Main {
public static void main(String[] args) {
new Main();
}
public Main() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
GlassPane glassPane = new GlassPane();
JFrame frame = new JFrame();
frame.setLayout(new GridLayout(2, 2, 8, 8));
frame.add(new MainPane(glassPane));
frame.add(new MainPane(glassPane));
frame.add(new MainPane(glassPane));
frame.add(new MainPane(glassPane));
frame.setGlassPane(glassPane);
glassPane.setVisible(true);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public interface Tracker {
public void addTrackable(Trackable trackable);
public void removeTrackable(Trackable trackable);
}
public interface Trackable {
public JComponent[] getTrackedComponents();
}
public class MainPane extends JPanel {
private JLabel label = new JLabel("Catch me if you can");
public MainPane(Tracker tracker) {
setLayout(new GridBagLayout());
setBorder(new CompoundBorder(new LineBorder(Color.DARK_GRAY, 1, true), new EmptyBorder(32, 32, 32, 32)));
add(label);
tracker.addTrackable(new Trackable() {
#Override
public JComponent[] getTrackedComponents() {
return new JComponent[]{label};
}
});
}
}
public class GlassPane extends JPanel implements Tracker {
private List<Trackable> trackables = new ArrayList<>(8);
private List<Color> masterColors = new ArrayList<>(Arrays.asList(new Color[]{
Color.RED,
Color.GREEN,
Color.BLUE,
Color.CYAN,
Color.DARK_GRAY,
Color.GRAY,
Color.MAGENTA,
Color.ORANGE,
Color.PINK,
Color.YELLOW,}));
public GlassPane() {
setOpaque(false);
}
#Override
public void addTrackable(Trackable trackable) {
trackables.add(trackable);
revalidate();
repaint();
}
#Override
public void removeTrackable(Trackable trackable) {
trackables.remove(trackable);
revalidate();
repaint();
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
g2d.setColor(Color.RED);
List<Color> colors = new ArrayList<>(masterColors);
for (Trackable trackable : trackables) {
for (JComponent component : trackable.getTrackedComponents()) {
if (colors.isEmpty()) {
colors = new ArrayList<>(masterColors);
}
g2d.setColor(colors.remove(0));
Rectangle relativeBounds = SwingUtilities.convertRectangle(component.getParent(), component.getBounds(), this);
g2d.draw(relativeBounds);
}
}
g2d.dispose();
}
}
}
Here is a new smipler example program, trying to keep as close to your code as possible, that uses the convertRectangle but I can't manage to run it correctly
int y = (int) (r.getY() + r.getHeight()); ... are you deliberately trying to offset the "overlay"? This seems weird to me.
Another issue is, how does the GlassPane know when the child has changed position/size
So, I modified your code, getting rid of the "modification" to the x/y position (so I'm 100% sure that the conversion between context spaces is correct) and added a ComponentListener to monitor changes to the "target" component
import java.awt.Color;
import java.awt.EventQueue;
import java.awt.Rectangle;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import java.awt.*;
import java.awt.event.ComponentAdapter;
import java.awt.event.ComponentEvent;
public class Main {
private Dimension pSize = new Dimension(100, 100);
private JFrame frame = new JFrame();
private JLabel content = new JLabel("Grief");
private JPanel content2 = new JPanel();
private SidePane sidePane = new SidePane();
private GlassPane glass = new GlassPane();
private Menu menu = new Menu();
public static void main(String[] args) {
new Main();
}
public Main() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
content.setBackground(Color.green);
content.setPreferredSize(pSize);
content.setOpaque(true);
//setup frame basics
frame.setPreferredSize(new Dimension(500, 500));
frame.setLayout(new BorderLayout());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocationRelativeTo(null);
frame.setGlassPane(glass);
frame.add(new MainPane());
// glass.setNewLocation();
// glass.revalidate();
frame.getGlassPane().setVisible(true);
// glass.setNewLocation();
frame.pack();
frame.setVisible(true);
}
});
}
public class MainPane extends JPanel {
public MainPane() {
//this.setBackground(Color.orange);
this.setLayout(new BorderLayout());
this.add(sidePane, BorderLayout.WEST);
this.add(menu, BorderLayout.NORTH);
}
}
public class SidePane extends JPanel {
public SidePane() {
FlowLayout f1 = new FlowLayout(FlowLayout.LEADING);
this.setLayout(f1);
this.setBackground(Color.blue);
this.add(content);
}
}
public class Menu extends JPanel {
public Menu() {
this.setBackground(Color.orange);
}
}
public class GlassPane extends JPanel {
private Rectangle target;
public GlassPane() {
this.setOpaque(false);
setLayout(null);
content2.setBackground(Color.BLACK);
content2.setPreferredSize(pSize);
content2.setOpaque(true);
add(content2);
content.addComponentListener(new ComponentAdapter() {
#Override
public void componentResized(ComponentEvent e) {
updateOverlay();
}
#Override
public void componentMoved(ComponentEvent e) {
updateOverlay();
}
});
}
protected void updateOverlay() {
// Rectangle t = new Rectangle();
// t.setBounds((int) content.getLocation().getX(), (int) content.getLocation().getY(), content.getWidth(), content.getHeight());
// Rectangle r = SwingUtilities.convertRectangle(content.getParent(), content.getBounds(), this);
// Rectangle r = SwingUtilities.convertRectangle(content.getParent(), content.getBounds(), this);
target = SwingUtilities.convertRectangle(content.getParent(), content.getBounds(), this);
content2.setBounds(target);
// r = SwingUtilities.convertRectangle(content.getParent(), t, this);
// int x = (int) r.getBounds().getX();
// x = (int) r.getX();
// int y = (int) (r.getY() + r.getHeight());
//
// content2.setBounds(x, y, 100, 100);
// this.add(content2);
}
#Override
public void paint(Graphics g) {
super.paint(g);
Graphics2D g2d = (Graphics2D) g.create();
if (target != null) {
g2d.setColor(Color.RED);
g2d.draw(target);
}
g2d.dispose();
}
}
}

If you have the coordinate within the component, transfer it to screen coordinates using your component's convertPointToScreen(). Afterwards you can transfer back to see where in the window it sits by using the frame's convertPointFromScreen().
Or eliminate one of the two steps by directly using convertPoint().

Fixed the positioning issue using #MadProgrammer 's method of SwingUtilities.convertRectangle and called a new method at the end of the constructor which positioned the tracker panel.
Created a separate class for the glass pane
private class GlassPane extends JPanel {
public GlassPane() {
this.setLayout(null);
}
public void setNewLocation() {
Rectangle r = SwingUtilities.convertRectangle(top, content.getBounds(), this);
JPanel content2 = new JPanel();
int x = (int) r.getBounds().getX();
x = (int) r.getX();
int y = (int) (r.getY() + r.getHeight() + 1);
content2.setBounds(x, y, 100,100);
this.add(content2);
}
}
And added a call to the new method setNewLocation() at the end of the constructor
public test() {
**...**
frame.pack();
frame.setVisible(true);
glass.setNewLocation();
}

How to make JScrollPane dynamically scroll to the end after adding components?

Here is my code for the ScrollPane
public class CustomScrollPane extends JScrollPane {
private static CustomScrollPane instance = null;
public CustomScrollPane () {
super(panel.getInstance()); // a panel that the scrollpane wraps around
this.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
// hide the vertical scroll bar
this.getVerticalScrollBar().setPreferredSize(new Dimension(0, 0));
}
public static CustomScrollPane getInstance() {
if (instance == null)
instance = new CustomScrollPane ();
return instance;
}
I tried to do getVerticalScrollbar.setValue(getVerticalScrollbar().getMaximum()) but it does not scroll to the end when I add JLabels to it. I'm trying to make it so that it will always scroll to the bottom of the screen once a new JLabel gets added to the panel. I din't use JTextArea as I want each line to have a different foreground color, so I used JLabels.
I also tried adding this method
public void scrollToBottom() { getVerticalScrollbar().getMaximum(); }
but it just freezes the ScrollPane and I am unable to scroll.
Any help would be appreciated!

I'm not sure what you hope to achieve by extending JScrollPane, not sure that it's really its core responsibility, after all, you could have its "viewport view" do it itself, for example...
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.GridLayout;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
public class Main {
public static void main(String[] args) {
new Main();
}
public Main() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
JFrame frame = new JFrame();
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
public TestPane() {
setLayout(new BorderLayout());
JPanel contentPane = new JPanel(new GridLayout(-1, 8));
for (int index = 0; index < 1000; index++) {
contentPane.add(new SqaurePane());
}
add(new JScrollPane(contentPane));
JButton top = new JButton("Top");
JButton bottom = new JButton("Bottom");
JPanel actionPane = new JPanel();
actionPane.add(top);
actionPane.add(bottom);
add(actionPane, BorderLayout.SOUTH);
top.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
contentPane.scrollRectToVisible(new Rectangle(0, 0, 1, 1));
}
});
bottom.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
contentPane.scrollRectToVisible(new Rectangle(0, contentPane.getHeight(), 0, 0));
}
});
}
#Override
public Dimension getPreferredSize() {
return new Dimension(400, 400);
}
}
static List<Color> COLORS = new ArrayList<>(Arrays.asList(new Color[] {
Color.BLACK,
Color.BLUE,
Color.CYAN,
Color.DARK_GRAY,
Color.GRAY,
Color.GREEN,
Color.LIGHT_GRAY,
Color.MAGENTA,
Color.ORANGE,
Color.PINK,
Color.RED,
Color.WHITE,
Color.YELLOW,
}));
public class SqaurePane extends JPanel {
public SqaurePane() {
Collections.shuffle(COLORS);
setBackground(COLORS.get(0));
}
#Override
public Dimension getPreferredSize() {
return new Dimension(50, 50);
}
}
}
The magic is right here...
top.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
contentPane.scrollRectToVisible(new Rectangle(0, 0, 1, 1));
}
});
bottom.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
contentPane.scrollRectToVisible(new Rectangle(0, contentPane.getHeight(), 0, 0));
}
});
Here, I'm asking the contentPane (which is the container holding all the squares) to "scroll to a visible rectangle" based on my needs
Now, in you case, when you add a new component to the "container", you would need to instruct the component to scroll to a position which would show the new component.
This is going to be a little more complicated as you will need to trigger a layout pass first, so you can get the new size of the container
Dynamic addition to the container...
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.GridLayout;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.Timer;
public class Main {
public static void main(String[] args) {
new Main();
}
public Main() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
JFrame frame = new JFrame();
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
public TestPane() {
setLayout(new BorderLayout());
JPanel contentPane = new JPanel(new GridLayout(-1, 8));
add(new JScrollPane(contentPane));
for (int index = 0; index < 8 * 8; index++) {
contentPane.add(new SqaurePane());
}
Timer timer = new Timer(500, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
SqaurePane sqaurePane = new SqaurePane();
contentPane.add(sqaurePane);
contentPane.revalidate();
// There is an issue with how the layout pass runs, this
// "seems" to be getting pushed onto the EDT later, which
// is messing up the scroll logic.
// So, instead, we push this on to the EDT to be executed
// "later" after the layout pass has run. Yes, I tried
// calling doLayout directly, but, for the first element
// of each row, it wouldn't work correctly
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
contentPane.scrollRectToVisible(new Rectangle(0, sqaurePane.getY(), 1, sqaurePane.getHeight()));
}
});
}
});
timer.start();
}
#Override
public Dimension getPreferredSize() {
return new Dimension(400, 400);
}
}
static List<Color> COLORS = new ArrayList<>(Arrays.asList(new Color[]{
Color.BLACK,
Color.BLUE,
Color.CYAN,
Color.DARK_GRAY,
Color.GRAY,
Color.GREEN,
Color.LIGHT_GRAY,
Color.MAGENTA,
Color.ORANGE,
Color.PINK,
Color.RED,
Color.WHITE,
Color.YELLOW,}));
public class SqaurePane extends JPanel {
public SqaurePane() {
Collections.shuffle(COLORS);
setBackground(COLORS.get(0));
}
#Override
public Dimension getPreferredSize() {
return new Dimension(50, 50);
}
}
}
Now, if you really wanted to decouple the concept, you could us a ContainerListener and react to the new component been added via it

Image not appearing in jbutton with wordGen

The image isn't being painted when this is run with WordGen, how do i fix this?
When I run this without wordgen I can get the image to appear. I'm not sure what i'm doing wrong since i'm not getting any errors.
Any help is appreciated.
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class tfot extends JComponent{
private static final long serialVersionUID = 1L;
public static void main(final String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
showGUI(args);
}
});
}
public static void showGUI(String[] args) {
JPanel displayPanel = new JPanel();
JButton okButton = new JButton("Did You Know?");
okButton.setFont(new Font("Times", Font.TRUETYPE_FONT, 100));
final JLabel jLab = new JLabel();
okButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
jLab.setText(wordGen());
}
});
JPanel content = new JPanel();
content.setLayout(new BorderLayout());
content.add(displayPanel, BorderLayout.CENTER);
content.add(okButton, BorderLayout.SOUTH);
content.add(jLab, BorderLayout.NORTH);
JFrame window = new JFrame("Window");
window.setContentPane(content);
window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
window.setSize(800, 600);
window.setLocation(400, 300);
window.setVisible(true);
}
#Override
public void paint(Graphics g) {
super.paint(g);
g.drawImage(Toolkit.getDefaultToolkit().getImage("Pictures/background1.png"), 0, 0, this);
}
public static String wordGen() {
String[] wordListOne = {"generic text","hi",};
int oneLength = wordListOne.length;
int rand1 = (int) (Math.random() * oneLength);
String phrase = wordListOne[rand1] + " ";
return phrase;
}
}

First...
Don't load resources or perform long running tasks within the paint methods, these may be called a number of times in quick succession. Instead, load the images before hand and paint them as needed...
public Tfot() {
setLayout(new BorderLayout());
try {
background = ImageIO.read(new File("pictures/background1.png"));
} catch (IOException ex) {
ex.printStackTrace();
}
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
if (background != null) {
g.drawImage(background, 0, 0, this);
}
}
Generally, you are discouraged from overriding paint and instead should use paintComponent, lots of reasons, but generally, this is where the background is painted...
Second...
You need to add Tfot to something that is displayable, otherwise it will never be painted
JFrame window = new JFrame("Window");
window.setContentPane(new Tfot());
window.add(content);
window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
window.setSize(800, 600);
window.setLocation(400, 300);
window.setVisible(true);
Thrid...
JPanel by default is not transparent, you need to set it's opaque property to false
JPanel displayPanel = new JPanel();
displayPanel.setOpaque(false);
//...
JPanel content = new JPanel();
content.setOpaque(false);
Then it will allow what ever is below it to show up (ie, the background image)
Take a look at Painting in AWT and Swing, Performing Custom Painting and Reading/Loading an Image for more details
Fourth...
You need to learn the language basics for embarking on advance topics like GUI and custom painting, without this basic knowledge, this topics will bite you hard.
You need to declare background as a instance field of the class Tfot
private BufferedImage background;
public Tfot() {
Updated - Fully runnable example
import java.awt.BorderLayout;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.imageio.ImageIO;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class Tfot extends JComponent {
private static final long serialVersionUID = 1L;
public static void main(final String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
showGUI(args);
}
});
}
public static void showGUI(String[] args) {
JPanel displayPanel = new JPanel();
displayPanel.setOpaque(false);
JButton okButton = new JButton("Did You Know?");
okButton.setFont(new Font("Times", Font.TRUETYPE_FONT, 100));
final JLabel jLab = new JLabel();
okButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
jLab.setText(wordGen());
}
});
JPanel content = new JPanel();
content.setOpaque(false);
content.setLayout(new BorderLayout());
content.add(displayPanel, BorderLayout.CENTER);
content.add(okButton, BorderLayout.SOUTH);
content.add(jLab, BorderLayout.NORTH);
Tfot tfot = new Tfot();
tfot.setLayout(new BorderLayout());
tfot.add(content);
JFrame window = new JFrame("Window");
window.setContentPane(tfot);
window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
window.setSize(800, 600);
window.setLocation(400, 300);
window.setVisible(true);
}
private BufferedImage background;
public Tfot() {
try {
background = ImageIO.read(new File("Pictures/background1.png"));
} catch (IOException ex) {
ex.printStackTrace();
}
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(background, 0, 0, this);
}
public static String wordGen() {
String[] wordListOne = {"generic text", "hi",};
int oneLength = wordListOne.length;
int rand1 = (int) (Math.random() * oneLength);
String phrase = wordListOne[rand1] + " ";
return phrase;
}
}

How to Close JInternalFrame when JButton click and show another JInternalFrame?

For Example:
When JButton1 click JInternalFrame1 Show on the JDesktopPane
And when JButton2 Click JInternalFrame1 Close and JInternalFrame2 Show on the JDesktopPane.
thx before
Edit: with code from comment
if (JInternalFrame1 == null) {
JInternalFrame1 = new FJInternalFrame();
Desktop.add(JInternalFrame1);
JInternalFrame1.toFront();
} else {
JInternalFrame1.dispose();
}

Take a look at this example. I created a custom JInternalFrame that has a different title every time you create a new frame. when you click on the button, a new one is created and the old one disapears
Here is the important code that may help you out. I add a new frame if the desktop size is equal to 0, other wise I remove the previous one, add a new frame, and revalidate
button.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if (desktop.getAllFrames().length == 0) {
desktop.add(new MyInternalFrame());
} else {
desktop.remove(0);
desktop.add(new MyInternalFrame());
revalidate();
repaint();
}
}
});
Here is the complete code. It's two different files.
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JDesktopPane;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class InternalFrameDemo1 extends JPanel {
JDesktopPane desktop;
JButton button;
public InternalFrameDemo1() {
desktop = new JDesktopPane();
button = new JButton("Get Next Frame");
setLayout(new BorderLayout());
add(desktop, BorderLayout.CENTER);
add(button, BorderLayout.SOUTH);
button.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if (desktop.getAllFrames().length == 0) {
desktop.add(new MyInternalFrame());
} else {
desktop.remove(0);
desktop.add(new MyInternalFrame());
revalidate();
repaint();
}
}
});
}
public static void createAndShowGui() {
JFrame frame = new JFrame();
frame.add(new InternalFrameDemo1());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocationByPlatform(true);
frame.pack();
frame.setVisible(true);
}
public Dimension getPreferredSize() {
return new Dimension(500, 500);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
import javax.swing.JInternalFrame;
public class MyInternalFrame extends JInternalFrame {
static int openFrameCount = 0;
static final int xOffset = 30, yOffset = 30;
public MyInternalFrame() {
super("Document #" + (++openFrameCount),
true, //resizable
true, //closable
true, //maximizable
true);//iconifiable
setSize(300,300);
setLocation(xOffset*openFrameCount, yOffset*openFrameCount);
setVisible(true);
}
}

JPanel in the middle of the frame

I'm trying to put my jpanel in the middle of the frame... so when the user try to change the size of the window frame, it remain in the middle...
something like this:
so if i change size it have to remain in the middle:
i Tried to change the layout of my contentPane with the BorderLayout and put my jpanel in the center position... but when i change size of my frame the panel go in the top left corner.
In my windows builder the situation is this:
my jpanel have to work exactly how works the redbox. i tried everything but the result is everytime the same:
this is my code:
package StudApp;
import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.util.ArrayList;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;
import javax.swing.JMenuBar;
import javax.swing.JMenu;
import javax.swing.JMenuItem;
import javax.swing.JTextPane;
import javax.swing.JLabel;
import java.awt.Font;
import javax.swing.SwingConstants;
import java.awt.Color;
import javax.swing.JTextArea;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
public class StudApp {
private JFrame frame;
private JPanel homeFirstRun;
private ArrayList<Corso> corsi = new ArrayList<Corso>();
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
new StudApp();
}
});
}
/**
* Create the frame.
*/
public StudApp() {
frame = new JFrame("Student Note");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setBounds(100, 100, 450, 300);
JMenuBar menuBar = new JMenuBar();
frame.setJMenuBar(menuBar);
JMenu menuHelp = new JMenu("Help");
menuBar.add(menuHelp);
JMenuItem menuIstrStud = new JMenuItem("Intructions Student Note");
menuIstrStud.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
frame.remove(homeFirstRun);
frame.revalidate();
frame.repaint();
homeFirstRun = null;
}
});
menuHelp.add(menuIstrStud);
homeFirstRun = new JPanel();
homeFirstRun.setBorder(new EmptyBorder(5, 5, 5, 5));
homeFirstRun.setLayout(null);
frame.getContentPane().add(homeFirstRun);
JLabel welcomeMessage = new JLabel("Welcome to Student Note");
welcomeMessage.setBounds(5, 5, 424, 18);
welcomeMessage.setForeground(Color.DARK_GRAY);
welcomeMessage.setHorizontalAlignment(SwingConstants.CENTER);
welcomeMessage.setFont(new Font("Verdana", Font.BOLD, 14));
homeFirstRun.add(welcomeMessage);
JTextArea welcomeTextArea = new JTextArea();
welcomeTextArea.setFont(new Font("Verdana", Font.PLAIN, 13));
welcomeTextArea.setText(" I think it's your first time here.\n\n"
+ " So the first step is to create a new course to\n insert your grades.\n\n"
+ " If you want my advice, read how this program\n works in the help section (it is very simple),\n "
+ "just 2 minutes ... believe me");
welcomeTextArea.setEditable(false);
welcomeTextArea.setBounds(27, 34, 381, 184);
homeFirstRun.add(welcomeTextArea);
frame.setVisible(true);
}
}

There are several ways to do this, but one of the easiest is to give the contentPane a GridBagLayout, and then add your JPanel of interest with no GridBagConstraints. If the JPanel of interest is the only thing added to this container, this will then place that JPanel into a central position.
e.g.,
import java.awt.*;
import javax.swing.*;
public class CentralPanel {
private static void createAndShowGui() {
JFrame frame = new JFrame("CentralPanel");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setContentPane(new MyContentPane());
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
class MyContentPane extends JPanel {
private static final int PREF_W = 700;
private static final int PREF_H = 550;
public MyContentPane() {
setLayout(new GridBagLayout());
add(new JPanelOfInterest());
}
#Override
public Dimension getPreferredSize() {
return new Dimension(PREF_W, PREF_H);
}
}
class JPanelOfInterest extends JPanel {
private static final int PREF_W = 400;
private static final int PREF_H = PREF_W;
public JPanelOfInterest() {
setBorder(BorderFactory.createTitledBorder("JPanel of Interest"));
}
#Override
public Dimension getPreferredSize() {
return new Dimension(PREF_W, PREF_H);
}
}