How can i unload a JPanel?

Hi, i have a JFrame with a JPanel.. i would like to know how to unload it after it's used, thanks....

From the JFrame JavaDoc:
void      remove(Component comp)
          Removes the specified component from the container.I am not sure if you need to get the content pane, and call remove( myJPanel ) on the content pane, or just simply call remove( myJPanel ) from the JFrame.
But, you can test that.
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How can I hide a JPanel?

I have some JPanels and using the mouse motion listeners you can scribble on them. I want to be able to switch between these panels but the problem is the drawings get wiped off when I use repaint() and frame.add(panel).
Any ideas how else I could try doing this?

Ok thanks everyone. I've taken the MyPanel class from here http://java.sun.com/docs/books/tutorial/uiswing/painting/step3.html
class MyPanel extends JPanel {
    private int squareX = 50;
    private int squareY = 50;
    private int squareW = 20;
    private int squareH = 20;
    public MyPanel() {
        setBorder(BorderFactory.createLineBorder(Color.black));
        addMouseListener(new MouseAdapter() {
            public void mousePressed(MouseEvent e) {
                moveSquare(e.getX(),e.getY());
        addMouseMotionListener(new MouseAdapter() {
            public void mouseDragged(MouseEvent e) {
                moveSquare(e.getX(),e.getY());
    private void moveSquare(int x, int y) {
        int OFFSET = 1;
        if ((squareX!=x) || (squareY!=y)) {
            repaint(squareX,squareY,squareW+OFFSET,squareH+OFFSET);
            squareX=x;
            squareY=y;
            repaint(squareX,squareY,squareW+OFFSET,squareH+OFFSET);
    public Dimension getPreferredSize() {
        return new Dimension(250,200);
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);
        g.drawString("This is my custom Panel!",10,20);
        g.setColor(Color.RED);
        g.fillRect(squareX,squareY,squareW,squareH);
        g.setColor(Color.BLACK);
        g.drawRect(squareX,squareY,squareW,squareH);
}Now if I use this class to make two panels, how can I hide one and bring the other one up and vice versa, using two buttons? setVisible() still doesn't work properly.
Here's the whole code.
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.SwingUtilities;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.BorderFactory;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseMotionListener;
import java.awt.event.MouseMotionAdapter;
public class PanelTest extends JFrame {
    private MyPanel panelOne;
    private MyPanel panelTwo;
    private BorderLayout layoutManager;
    private PanelTest() {
        layoutManager = new BorderLayout();
        this.setLayout(layoutManager);
        panelOne = new MyPanel();
        panelTwo = new MyPanel();
        panelOne.add(new JLabel("This is Panel One"));
        panelTwo.add(new JLabel("This is Panel Two"));
        setCurrentPanel(panelOne);
        JButton switchButton = new JButton("Switch");
        switchButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                if(getCurrentPanel() == panelOne) {
                    setCurrentPanel(panelTwo);
                } else {
                    setCurrentPanel(panelOne);
        this.getContentPane().add(switchButton, BorderLayout.SOUTH);
        this.pack();
        this.setVisible(true);
    private void setCurrentPanel(MyPanel panel) {
        this.getContentPane().add(panel, BorderLayout.CENTER);
        panel.revalidate();
        panel.repaint();
    private JPanel getCurrentPanel() {
        return (JPanel)layoutManager.getLayoutComponent(BorderLayout.CENTER);
    public static void main(String[] args) {
        new PanelTest();
class MyPanel extends JPanel {
    private int squareX = 50;
    private int squareY = 50;
    private int squareW = 20;
    private int squareH = 20;
    public MyPanel() {
        setBorder(BorderFactory.createLineBorder(Color.black));
        addMouseListener(new MouseAdapter() {
            public void mousePressed(MouseEvent e) {
                moveSquare(e.getX(),e.getY());
        addMouseMotionListener(new MouseAdapter() {
            public void mouseDragged(MouseEvent e) {
                moveSquare(e.getX(),e.getY());
    private void moveSquare(int x, int y) {
        int OFFSET = 1;
        if ((squareX!=x) || (squareY!=y)) {
            repaint(squareX,squareY,squareW+OFFSET,squareH+OFFSET);
            squareX=x;
            squareY=y;
            repaint(squareX,squareY,squareW+OFFSET,squareH+OFFSET);
    public Dimension getPreferredSize() {
        return new Dimension(250,200);
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);
        g.setColor(Color.RED);
        g.fillRect(squareX,squareY,squareW,squareH);
        g.setColor(Color.BLACK);
        g.drawRect(squareX,squareY,squareW,squareH);
}Edited by: atom.bomb on Mar 30, 2010 11:25 AM

How can I close a JPanel

Hello,
I have a GUI that uses a JPanel to acquire user information and returns it to the main GUI class, after I get that information I want to close automatically that JPanel with out closing the whole application, how can I do that?
I have been looking for a close method but I can not find one, any suggestions will be greatly appreciated.
Thanks.

Never mind,
I guess I did not try the dispose() method yet, thanks anyway!!!!!

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Sharma,
Here's step by step what I did after your last post:
1) I re-installed Flash from my account.
2) I Deleted the other account, along with all files associated with it.
3) I created a new account with administrator privilege.
4) I logged off my account and logged onto the new account.
5) I started WINDOWS explorer and navigated to windows/system32/Macromed/Flash
6) I ran FlashUtil10c (See Screen Shot One)
7) Clicked "Install Now", program ran and I got a box that indicated it was 100% complete.
8) As I watched, FlashUtil10c, Flash10c.ocx and uninstall_activeX all three disappeared from the folder. (See Screen Shot 2)
9) Logged 0ff the newly created account and logged back into my account.
10) Tried to access a game that required flash and got the screen in Screen Shot 3.
11) Re-installed Flash from my account.
I'm right back where I started. This has got to be a common thing for people to do. Where am I going wrong? The installer I'm using is "Install_flash_player_10_active_x" that I downloaded from a site I got with my free license and about which Adobe declared: "You may not share the above link, share information with others, or publish the above link on websites, blogs, or by any other means that can be publicly accessed. "
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How can I make my JPanels appear overlapped on each other?

Hi there
In my program i have say 3 JPanels inside a one big JPanel (container), and I want those 3 JPanels inside, appear in an overlapped fashion. Obviously the layout of the container jpanel does not allow me to that. Is there a work around to that?
I am aware of the JLayeredPane, but as far as i know i cannot add a JPanel into it. Or can I?
Any help appreciated.

You can add JPanels to a container in an overlapped fashion, when you switch off the layout manger of the container by:
bigPanel.setLayout(null);then you have to layout the container yourself by calling the
setBounds(x,y,width,height) method on the 3 panels.
But I don't know how to control the z-order of the panels.
I think using JLayeredPane is the better solution.
JLayerdPane definitely works with JPanels.

How can I Print a JPanel including all added Components?

Hello dear saviours,
I have a JPanel object which is responsible for displaying a Graph.
I need to Print the Components of this JPanel as close to what they look like to the user as possible.
I thought about casting the JPanel into an Image of some kind, but couldn't find anything but how to add am Image to a JPanel (God damned search engines :-).
But wait, this gets more interesting!
I need to have control over the scale of the Printed matterial.
I want the option to choose between a single page and dividing the drawing the JPanel displays into Multiple-Pages.
In both cases I need full details of all the data (Nodes, Arcs, Text describing the various Nodes and Arcs names or type, etc.).Keeping the sizes of all these components is also important (that means, I don't want the nodes to be tinny-winny and the Fonts to be twice as large as the nodes and so on...).
Attached is the code of the PrintUtillity class I created as an API for printing the JPanel data:
package ild;
import java.awt.*;
import javax.swing.*;
import java.awt.print.*;
/** A simple utility class that lets you very simply print
* an arbitrary component. Just pass the component to the
* PrintUtilities.printComponent. The component you want to
* print doesn't need a print method and doesn't have to
* implement any interface or do anything special at all.
* <P>
* If you are going to be printing many times, it is marginally more
* efficient to first do the following:
* <PRE>
* PrintUtilities printHelper = new PrintUtilities(theComponent);
* </PRE>
* then later do printHelper.print(). But this is a very tiny
* difference, so in most cases just do the simpler
* PrintUtilities.printComponent(componentToBePrinted).
* 7/99 Marty Hall, http://www.apl.jhu.edu/~hall/java/
* May be freely used or adapted.
public class PrintUtilities implements Printable {
private Component componentToBePrinted;
public PrintUtilities(Component componentToBePrinted) {
this.componentToBePrinted = componentToBePrinted;
public static void printComponent(Component c) {
new PrintUtilities(c).print();
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PrinterJob printJob = PrinterJob.getPrinterJob();
printJob.setPrintable(this);
if (printJob.printDialog())
try {
printJob.print();
} catch(PrinterException pe) {
System.out.println("Error printing: " + pe);
public int print(Graphics g, PageFormat pageFormat, int pageIndex) {
if (pageIndex > 0) {
return(NO_SUCH_PAGE);
} else {
Graphics2D g2d = (Graphics2D)g;
// double scale = 2;
// g2d.translate(pageFormat.getImageableX(), pageFormat.getImageableY());
double scaleFactor = java.lang.Math.min((double)this.componentToBePrinted.getSize().width/(double)(pageFormat.getImageableWidth()),
(double)this.componentToBePrinted.getSize().height/(double)(pageFormat.getImageableHeight()));
g2d.translate(pageFormat.getImageableX(), pageFormat.getImageableY());
g2d.scale(1.0/scaleFactor,1.0/scaleFactor);
// disableDoubleBuffering(componentToBePrinted);
componentToBePrinted.paint(g2d);
enableDoubleBuffering(componentToBePrinted);
return(PAGE_EXISTS);
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* any of the containers have double buffering turned on.
* So this turns if off globally.
* @see enableDoubleBuffering
public static void disableDoubleBuffering(Component c) {
RepaintManager currentManager = RepaintManager.currentManager(c);
currentManager.setDoubleBufferingEnabled(false);
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public static void enableDoubleBuffering(Component c) {
RepaintManager currentManager = RepaintManager.currentManager(c);
currentManager.setDoubleBufferingEnabled(true);

That's a nice utility, but my JPanel gets truncated when printed. Is there a way to print a JPanel in full.

How can i unload a sequence from another sequence

Hello,
i have a sequence which is running in a loop. At a specified point the sequence executes an ActiveX-call an runs "Test UUTs" with a sequence-name that is passed with a variable.
When "TestUUT" is running then first the SequenceFileLoad of the new sequence is executed and after that the Mainsequence. Thats all good up to here.
But the next time when i call the execute "Test UUTs" then the file is already in loaded and no SequenceFileLoad is running.
So my question is: What do i have to call/run that the loaded sequence is leaving the memory with SequenceFileUnload and the next time when i run "TestUUTs" is completely new loaded?
Thx for your help
Attached a screenshot of how i execute the "TestUUTs"
Attachments:
Clipboard01.jpg ‏42 KB

The thing is, i only want to execute the SequenceFileUnload when i have a new sequence name in the variable of "Execute Test UUTs".
If the sequence is loaded and executed again, then i dont want to run SequenceFileLoad again.
Thats why i want to execute an "unload"-thing somehow.
It looks like this:
string seqname= sequence1
call execute "Test UUTs" (seqname)
SequenceFileLoad(sequence1)
execute(seqname)
call execute "Test UUTs" (seqname)
//no SequenceFileLoad because its already loaded
execute(seqname)
call execute "Test UUTs" (seqname)
//no SequenceFileLoad because its already loaded
execute(seqname)
string seqname= sequence2
SequenceFileUNLoad(sequence1)
SequenceFileLoad(sequence2)
execute(seqname)
call execute "Test UUTs" (seqname)
//no SequenceFileLoad because its already loaded
execute(seqname)

How can you unload your iphone contacts to a computer

When I purchased my phone from ATT, they copied my contacts from my existing phone memory card to the new iphone. When looking in the iphone, the names aren't first and last, they're just one name so instead of 'Bob Jones' it came as 'Jones;Bob/H - it was Bob Jones Home phone number.' . No way to sort by 1st name because there isn't anyfirst name.
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Ron

Previous to starting this, I synced to icloud. And I believe that itunes backed up all the info to windows contacts, so they were in 2 places and the phone.
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Ron

How can I unload data to ASCII fixed-format or delimited files,

Hello,
SQL*Loader loads data from ASCII fixed-format or delimited files. Is there such utility to unload data from Oracle database ?
Agnieszka

No. The Export utility will dump data out but not into an ascii file.
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Check out the ULT_FILE package - this will allow you to write some SQL code which will do the job you want.
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R

I just want to know how can i unload may balance.? Im in japan store but my friend gave me itunes card from canada. I still have 145 yen. How can i unload that balance i want to change to canada store

A

Contact iTunes Customer Service and request assistance
Use this Link > Apple Support iTunes Store Contact
Note: iTunes Gift Cards are only Valid in Country of Issue

HT1925 i have delete whatsapp by mistake and now the new version is not compatible with my iphone, how can i take it back again ?

Hello i need help, i unloaded the new version of whatsapp and now is not working because my phone is not compatible, i delete it, and now i can not unloaded it again ! how can i unload the old version again ? thanks

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This question, by the way, would have better been posted in the Using iPhone forum rather than here in the QuickTime forum.
Regards.

How can I display JTextFields correctly on a JPanel using GridBagLayout?

I had some inputfields on a JPanel using the boxLayout. All was ok. Then I decided to change the panellayout to GridBagLayout. The JLabel fields are displayed correctly but the JTextField aren't. They are at the JPanel but have a size of 0??? So we cannot see what we type in these fields... Even when I put some text in the field before putting it on the panel.
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here is a shortcut of my code:
private Dimension sFieldSize10 = new Dimension(80, 20);
// Create and instantiate Selection Fields
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private JTextField searchAbrText = new JTextField();
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searchAbrNumber.createToolTip();
searchAbrNumber.setToolTipText("enter the AbrNumber.");
searchAbrNumber.setPreferredSize(sFieldSize10);
searchAbrNumber.setMaximumSize(sFieldSize10);
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pSubset = new JPanel();
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pSubset.setLayout(new GridBagLayout());
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gbc.gridy = 0;
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pSubset.add(lSearchAbrNumber, gbc);
// also tried inserting this statement
// searchAbrNumber.setText("0000000");
// without success
pSubset.add(searchAbrNumber,gbc);
pSubset.add(lSearchAbrText, gbc);
pSubset.add(searchAbrText, gbc);
gbc.gridy = 1;
pSubset.add(lSearchClassCode, gbc);
pSubset.add(searchClassCode, gbc);
pSubset.add(butSearch, gbc);
}

import java.awt.*;
import java.awt.event.*;
import javax .swing.*;
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public static void main(String[] args) {
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      labelThree = new JLabel("Label Three"),
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      tfThree = new JTextField(),
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fields[i].setPreferredSize(fieldSize);
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JPanel panel = new JPanel(gridbag);
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gbc.weightx = 1.0;
gbc.weighty = 1.0;
gbc.insets = new Insets(5,5,5,5);
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panel.add(labelFour, gbc);
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final int DELTA_X = 25;
int oldWidth, newWidth;
public void actionPerformed(ActionEvent e) {
JButton button = (JButton)e.getSource();
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How can i save the data in a jpanel form to a .txt document

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please help me..

each time when i fill the form and click save button ,all the data in the form should be written to a text file and each time when i repeat it should append to the old data in the text file.the elements in the form should be seperated by pipe delimeter.
thanks for your patience..

How can i put one scene into JPanel of the swing?

how can i put one scene into JPanel of the swing?

980571 wrote:
ty for the information but i have a problen with JFXpanel when i try to into a panel it doesnt display insideSorry to hear that. If you want assistance with the code, feel free to post the relevant parts of it. Make sure to use \ tags when you do.

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Hi!
I want to open a MFC window, then with the HWND , i want to open java subwindow created inside the MFC window with the HWND, i wonder if there is a way. how can i transform the HWND into jpanel or jframe instance.

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How can i unload a JPanel?

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