JFrame

Parent JFrame does not repaint a when processing is going on in child JFrame.
My problem is:
1. I have a JFrame which is root frame for my application. Then on click of a button, a new JFrame opens up which is child of the root frame.
2. This new Frame is used for searching. Now when I key-in a search criteria and click on Search button, reqest goes to server. Now during the processing of teh request if I move the child frame over the parent frame (root in this case), then it (root) does not repaint itself till the request processing at the child frame finishes.

1) Generally an application only has a single JFrame. The child frames are typically JDialogs, not JFrames.
2) To execute a long running task you need to use Threads so the GUI Event Thread is free to respond to GUI events. [url http://java.sun.com/docs/books/tutorial/uiswing/misc/threads.html]How to Use Threads.

Similar Messages

Problem with threads in JFrame

Hy everyone...i have a small problem when i try to insert clock in my JFrame , because all i get is an empty text field.
What i do is that i create inner class that extends Thread and implements Runnable , but i dont know ... i saw some examples on the intrnet...but they are all for Applets...
Does any one know how i can implement this in JFrame (JTextField in JFrame).
Actually any material on threads in JFrame or JPanel would be great....THNX.

For my original bad thread version, I have rewritten it mimicking javax.swing.Timer
implementation, reducing average CPU usage to 2 - 3%.
Will you try this:
import javax.swing.*;
import java.awt.*;
import java.text.*;
import java.util.*;
public class SamurayClockW{
JFrame frame;
Container con;
ClockTextFieldW ctf;
public SamurayClockW(){
    frame = new JFrame();
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    con = frame.getContentPane();
    ctf = new ClockTextFieldW();
    con.add(ctf, BorderLayout.SOUTH);
    frame.setBounds(100, 100, 300, 300);
    frame.setVisible(true);
    ctf.start();
public static void main(String[] args){
    new SamurayClockW();
class ClockTextFieldW extends JTextField implements Runnable{
String clock;
boolean running;
public ClockTextFieldW(){
    setEditable(false);
    setHorizontalAlignment(RIGHT);
public synchronized void start(){
    running = true;
    Thread t = new Thread(this);
    t.start();
public synchronized void stop(){
    running = false;
public synchronized void run(){
    SimpleDateFormat sdf = new SimpleDateFormat("HH:mm:ss");
    try{
      while (running){
        clock = sdf.format(new Date());
        SwingUtilities.invokeLater(new Runnable(){
          public void run(){
            setText(clock);
        try{
          wait(1000);
        catch (InterruptedException ie){
          ie.printStackTrace();
    catch (ThreadDeath td){
      running = false;
}

Can not refresh JFrame

I am new to Java programming however I have undertaken a project to build a serial communication application using J2SE 1.4 w/javax.comm API. I am having a problem in which I detect a button click with action listener and post a JOptionPane message. Once the JOptionPane is closed I execute the desired task however the pane leaves a grey block overlaying the JFrame. I have been unable to figure out how to repaint the JFrame. Can anyone give me suggestions?
Thanks
D :-)

A more active example:
if (JOptionPane.showConfirmDialog(null, "Are you
u sure?",
"Are you sure?", JOptionPane.YES_NO_OPTION) ==
N) == 0) {
Thread t = new Thread(new Runnable() {
public void run() {
// Do your work in here!
t.start();
}This will leave the JFrame completely free to do
whatever else it wants, so if you want it to do
nothing, you may want to write a 'disableFrame()'
method which disables everything, and perhaps stick a
JProgressBar at the bottom to show that something's
going on. This needs to be controlled via the 'run()'
method.
Let me know if this helps.
RichardThanks Richard.
Do I have to stop the thread explicitly. The task looks for a serial event.

Need to convert JApplet to JFrame

I need to write code for where I have 60 balls bouncing around inside a window. The client will then be able to select a button and it will pull out a ball with the number 1-60 written on it. The user will be able to do this up to 7 times. Each time it is done the past numbers that have already appeared can not reappear. What I am stuck on right now is geting my balls into a JFrame. Can anyone give advice or show how to. I currently have my 60 balls running in a JApplet. Here is the JAVA code and the HTML code. Thanks!
Here is the JAVA code
import java.awt.*;
import java.applet.*;
import java.util.*;
import javax.swing.*;
class CollideBall{
int width, height;
public static final int diameter=20;
//coordinates and value of increment
double x, y, xinc, yinc, coll_x, coll_y;
boolean collide;
Color color;
Graphics g;
Rectangle r;
//the constructor
public CollideBall(int w, int h, int x, int y, double xinc, double yinc, Color c){
width=w;
height=h;
this.x=x;
this.y=y;
this.xinc=xinc;
this.yinc=yinc;
color=c;
r=new Rectangle(150,80,130,90);
public double getCenterX() {return x+diameter/2;}
public double getCenterY() {return y+diameter/2;}
public void alterRect(int x, int y, int w, int h){
r.setLocation(x,y);
r.setSize(w,h);
public void move(){
if (collide){
double xvect=coll_x-getCenterX();
double yvect=coll_y-getCenterY();
if((xinc>0 && xvect>0) || (xinc<0 && xvect<0))
xinc=-xinc;
if((yinc>0 && yvect>0) || (yinc<0 && yvect<0))
yinc=-yinc;
collide=false;
x+=xinc;
y+=yinc;
//when the ball bumps against a boundary, it bounces off
if(x<6 || x>width-diameter){
xinc=-xinc;
x+=xinc;
if(y<6 || y>height-diameter){
yinc=-yinc;
y+=yinc;
//cast ball coordinates to integers
int x=(int)this.x;
int y=(int)this.y;
//bounce off the obstacle
//left border
if(x>r.x-diameter&&x<r.x-diameter+7&&xinc>0&&y>r.y-diameter&&y<r.y+r.height){
xinc=-xinc;
x+=xinc;
//right border
if(x<r.x+r.width&&x>r.x+r.width-7&&xinc<0&&y>r.y-diameter&&y<r.y+r.height){
xinc=-xinc;
x+=xinc;
//upper border
if(y>r.y-diameter&&y<r.y-diameter+7&&yinc>0&&x>r.x-diameter&&x<r.x+r.width){
yinc=-yinc;
y+=yinc;
//bottom border
if(y<r.y+r.height&&y>r.y+r.height-7&&yinc<0&&x>r.x-diameter&&x<r.x+r.width){
yinc=-yinc;
y+=yinc;
public void hit(CollideBall b){
if(!collide){
coll_x=b.getCenterX();
coll_y=b.getCenterY();
collide=true;
public void paint(Graphics gr){
g=gr;
g.setColor(color);
//the coordinates in fillOval have to be int, so we cast
//explicitly from double to int
g.fillOval((int)x,(int)y,diameter,diameter);
g.setColor(Color.white);
g.drawArc((int)x,(int)y,diameter,diameter,45,180);
g.setColor(Color.darkGray);
g.drawArc((int)x,(int)y,diameter,diameter,225,180);
public class BouncingBalls extends Applet implements Runnable {
Thread runner;
Image Buffer;
Graphics gBuffer;
CollideBall ball[];
//Obstacle o;
//how many balls?
static final int MAX=60;
boolean intro=true,drag,shiftW,shiftN,shiftE,shiftS;
boolean shiftNW,shiftSW,shiftNE,shiftSE;
int xtemp,ytemp,startx,starty;
int west, north, east, south;
public void init() {
Buffer=createImage(getSize().width,getSize().height);
gBuffer=Buffer.getGraphics();
ball=new CollideBall[MAX];
int w=getSize().width-5;
int h=getSize().height-5;
//our balls have different start coordinates, increment values
//(speed, direction) and colors
for (int i = 0;i<60;i++){
ball=new CollideBall(w,h,50+i,20+i,1.5,2.0,Color.white);
/* ball[1]=new CollideBall(w,h,60,210,2.0,-3.0,Color.red);
ball[2]=new CollideBall(w,h,15,70,-2.0,-2.5,Color.pink);
ball[3]=new CollideBall(w,h,150,30,-2.7,-2.0,Color.cyan);
ball[4]=new CollideBall(w,h,210,30,2.2,-3.5,Color.magenta);
ball[5]=new CollideBall(w,h,360,170,2.2,-1.5,Color.yellow);
ball[6]=new CollideBall(w,h,210,180,-1.2,-2.5,Color.blue);
ball[7]=new CollideBall(w,h,330,30,-2.2,-1.8,Color.green);
ball[8]=new CollideBall(w,h,180,220,-2.2,-1.8,Color.black);
ball[9]=new CollideBall(w,h,330,130,-2.2,-1.8,Color.gray);
ball[10]=new CollideBall(w,h,330,10,-2.1,-2.0,Color.gray);
ball[11]=new CollideBall(w,h,220,230,-1.2,-1.8,Color.gray);
ball[12]=new CollideBall(w,h,230,60,-2.3,-2.5,Color.gray);
ball[13]=new CollideBall(w,h,320,230,-2.2,-1.8,Color.gray);
ball[14]=new CollideBall(w,h,130,300,-2.7,-3.0,Color.gray);
ball[15]=new CollideBall(w,h,210,90,-2.0,-1.8,Color.gray);*/
public void start(){
if (runner == null) {
runner = new Thread (this);
runner.start();
/* public void stop(){
if (runner != null) {
runner.stop();
runner = null;
public void run(){
while(true) {
Thread.currentThread().setPriority(Thread.MAX_PRIORITY);
try {runner.sleep(15);}
catch (Exception e) { }
//move our balls around
for(int i=0;i<MAX;i++)
ball[i].move();
handleCollision();
repaint();
boolean collide(CollideBall b1, CollideBall b2){
double wx=b1.getCenterX()-b2.getCenterX();
double wy=b1.getCenterY()-b2.getCenterY();
//we calculate the distance between the centers two
//colliding balls (theorem of Pythagoras)
double distance=Math.sqrt(wx*wx+wy*wy);
if(distance<b1.diameter)
return true;
return false;
private void handleCollision()
//we iterate through all the balls, checking for collision
for(int i=0;i<MAX;i++)
for(int j=0;j<MAX;j++)
if(i!=j)
if(collide(ball[i], ball[j]))
ball[i].hit(ball[j]);
ball[j].hit(ball[i]);
public void update(Graphics g)
paint(g);
public void paint(Graphics g)
gBuffer.setColor(Color.lightGray);
gBuffer.fillRect(0,0,getSize().width,getSize().height);
gBuffer.draw3DRect(5,5,getSize().width-10,getSize().height-10,false);
//paint our balls
for(int i=0;i<MAX;i++)
ball[i].paint(gBuffer);
g.drawImage (Buffer,0,0, this);
Here is the HTML code
<html>
<body bgcolor="gray">
<br><br>
<div align="center">
<applet code="BouncingBalls.class" width="1000" height="650"></applet>
</div>
</body>
</html>

In the future, Swing related questions should be posted in the Swing forum.
First you need to convert your custom painting. This is done by overriding the paintComponent() method of JComponent or JPanel. Read the Swing tutorial on [Custom Painting|http://java.sun.com/docs/books/tutorial/uiswing/TOC.html].
If you need further help then you need to create a [Short, Self Contained, Compilable and Executable, Example Program (SSCCE)|http://homepage1.nifty.com/algafield/sscce.html], that demonstrates the incorrect behaviour.
Don't forget to use the [Code Formatting Tags|http://forum.java.sun.com/help.jspa?sec=formatting], so the posted code retains its original formatting.

Problem with Paining in a Panel in a JFrame.

So I can paint directly on a JFrame, and I can paint on a class that extends Panel, and put the Panel on a JFrame. But if I try to Repaint the Panel it won't show on the JFrame. Do I have to do anything to the JFrame to show the changes to the objects inside as well?

I'm not sure if you've done this, but don't change the paint method when using Swing components, use paintComponent instead. By default, the JFrame will paint its children. Just remember whenever overriding any of the paintComponent methods to call super.paintComponent(g) first.

Problem with IconImage for JFrame

If I create an BufferedImage by ImageIO.read for example and then call getScaledInstance on this image and set the scaled Image to a JFrame as the IconImage (via setIconImage(Image image)), the application hangs.
Has anyone else this problem?

ok ok, i read it and now think that this is a sscce:
import java.awt.Image;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
public class Start
     public static void main(String[] args)
          final JFrame frame = new JFrame();
          final Image image, imageScaled;
          try
               image = ImageIO.read(new File("test.png"));
               imageScaled = image.getScaledInstance(8, 8, Image.SCALE_DEFAULT);
               frame.add(new JLabel(new ImageIcon(image)));
               //frame.setIconImage(image); works
               frame.setIconImage(imageScaled); // works not
               frame.pack();
               frame.setVisible(true);
          catch (IOException e)
               System.err.println(e.getMessage());
               e.printStackTrace(System.err);
}

Problem with display of JFrame

I have a run opperation in which i call a method that creates a j frame and displays it. all the j frame is used for is displaying the text "adding sample data...". It works fine when I have my main window open but when I have my layout editor open, the JFrame shows up grayed out. It clears after my samples are added. I have no Idea why it wont display correctly and I was just wondering if you had any ideas as to what whould cause this to happen. Thanks

I can't be sure without seeing your code, or without more information about what it is your doing, but the problem could be threading. Is the JFrame that's showing up grayed out just supposed to tell the user to basically "please wait while I do something", and then dissapear after it's done working? If so, you should probably use a JDialog. In any case, try wrapping the code that opens the window in this:
Thread opener new Thread(new Runnable(){
public void run()
// ... put your code that opens the window in here. such as myFrame.setVisible(true);
opener.start();

Problem with backspace on JFrame

Hello,
I have a problem on a JFrame. Indeed, I add a keyListener to the frame, but the "Bakcspace" don't work. There is anything when a I press on Backspace (with KeyTyped, KeyReleased and KeyPressed). All other keys are working.
Thanks.

the solution of the problem is :
Version note: This page reflects the focus API introduced in released 1.4. As of that release, the focus subsystem consumes focus traversal keys, such as Tab and Shift Tab. If you need to prevent the focus traversal keys from being consumed, you can call
component.setFocusTraversalKeysEnabled(false)
on the component that is firing the key events. Your program must then handle focus traversal on its own. Alternatively, you can use a KeyEventDispatcher to pre-listen to all key events. The focus page (in the Creating a GUI with JFC/Swing trail) has detailed information on the focus subsystem.

Problem with jDialog in a JFrame

Hello to everyone...i'm newby java GUI developer, and i've got a problem with a JDialog within a JFrame...
I made a JFrame which creates a new customized JDialog in his contructor, like this:
MioJdialog dlg = new MioJdialog(this, true);
dlg.setVisible(true);
...The "MioJdialog" class store his JFrame parent under a private attribute, in this way:
class MioJdialog {...
private Frame parent;
public MioJdialog (Frame parent, boolean modal){
this.parent=parent;
....}and here's the problem: when i try to close the parent JFrame with a command like this:
parent.dispose();
( in order to close the whole window), sometimes happens that the JFrame is still visible on the screen...and i don't know why...
got some hints?
thanks to everyone!
Edited by: akyra on Jan 14, 2008 4:36 AM
Edited by: akyra on Jan 14, 2008 4:37 AM
Edited by: akyra on Jan 14, 2008 4:37 AM

If you need further help then you need to create a "Short, Self Contained, Compilable and Executable, Example Program (SSCCE)", that demonstrates the incorrect behaviour.
http://homepage1.nifty.com/algafield/sscce.html
Don't forget to use the "Code Formatting Tags", so the posted code retains its original formatting.
http://forum.java.sun.com/help.jspa?sec=formatting

Problem with setContentPane() in JFrame class

I recently discovered a problem with the setContentPane method in the JFrame class. When I use setContentPane(Container ..), the previously existing contentPane remains in the stack. I have tried nullifying getContentPane(), and all manner of things, but, each time I use setContentPane, I have another instance of a JPanel in the stack.
I'm using code similar to setContentPane(new CustomJPanel()); and each time the user changes screens, and a similar call to that is made, the old CustomJPanel instance remains in the stack. Can anyone suggest a way around this? On their own the panels do not take up very much memory, but after several hours of usage, they will build up.

I tried what you suggested; it only resulted in a huge performance decrease. The problem with memory allocation is still there.
Here is the method I use to switch screens in my app:
public static void changeScreen (JPanel panel){
          try{
               appFrame.setTitle("Wordinary : \""+getTitle()+"\"");
               appFrame.setContentPane(panel);
               appFrame.setSize(appFrame.getContentPane().getPreferredSize());
               appFrame.getContentPane().setBackground(backColour);
               for (int i = 0; i < appFrame.getContentPane().getComponents().length; i++)
                    appFrame.getContentPane().getComponents().setForeground(textColour);
               //System.out.println("Background colour set to "+backColour+" text colour set to "+textColour);
               appFrame.validate();
          catch (Exception e){
               //System.out.println("change");
               e.printStackTrace();
And it is called like this:
changeScreen(new AddWordPanel());The instantiation of the new instance is what is causing the memory problems, but I can't think of a way around it.

Problem with JPanel in JFrame

hai ashrivastava..
thank u for sending this one..now i got some more problems with that screen .. actually i am added one JPanel to JFrame with BorderLayout at south..the problem is when i am drawing diagram..the part of diagram bellow JPanel is now not visible...and one more problem is ,after adding 6 ro 7 buttons remaing buttons are not vissible..how to increase the size of that JPanel...to add that JPanel i used bellow code
JFrame f = new JFrame();
JPanel panel = new JPanel();
f.getContentPane().add(BorderLayout.SOUTH, panel);

Hi
JFrame f = new JFrame();
JPanel panel = new JPanel();
// Add this line to ur code with ur requiredWidth and requiredHeight
panel.setPreferredSize(new Dimension(requiredWidth,requiredHeight));
f.getContentPane().add(BorderLayout.SOUTH, panel);
This should solve ur problem
Ashish

Problem with JFrame and busy/wait Cursor

Hi -- I'm trying to set a JFrame's cursor to be the busy cursor,
for the duration of some operation (usually just a few seconds).
I can get it to work in some situations, but not others.
Timing does seem to be an issue.
There are thousands of posts on the BugParade, but
in general Sun indicates this is not a bug. I just need
a work-around.
I've written a test program below to demonstrate the problem.
I have the problem on Solaris, running with both J2SE 1.3 and 1.4.
I have not tested on Windows yet.
When you run the following code, three JFrames will be opened,
each with the same 5 buttons. The first "F1" listens to its own
buttons, and works fine. The other two (F2 and F3) listen
to each other's buttons.
The "BUSY" button simply sets the cursor on its listener
to the busy cursor. The "DONE" button sets it to the
default cursor. These work fine.
The "SLEEP" button sets the cursor, sleeps for 3 seconds,
and sets it back. This does not work.
The "INVOKE LATER" button does the same thing,
except is uses invokeLater to sleep and set the
cursor back. This also does not work.
The "DELAY" button sleeps for 3 seconds (giving you
time to move the mouse into the other (listerner's)
window, and then it behaves just like the "SLEEP"
button. This works.
Any ideas would be appreciated, thanks.
-J
import java.awt.BorderLayout;
import java.awt.Cursor;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class BusyFrameTest implements ActionListener
private static Cursor busy = Cursor.getPredefinedCursor (Cursor.WAIT_CURSOR);
private static Cursor done = Cursor.getDefaultCursor();
JFrame frame;
JButton[] buttons;
public BusyFrameTest (String title)
frame = new JFrame (title);
buttons = new JButton[5];
buttons[0] = new JButton ("BUSY");
buttons[1] = new JButton ("DONE");
buttons[2] = new JButton ("SLEEP");
buttons[3] = new JButton ("INVOKE LATER");
buttons[4] = new JButton ("DELAY");
JPanel buttonPanel = new JPanel();
for (int i = 0; i < buttons.length; i++)
buttonPanel.add (buttons);
frame.getContentPane().add (buttonPanel);
frame.pack();
frame.setVisible (true);
public void addListeners (ActionListener listener)
for (int i = 0; i < buttons.length; i++)
buttons[i].addActionListener (listener);
public void actionPerformed (ActionEvent e)
System.out.print (frame.getTitle() + ": " + e.getActionCommand());
if (e.getActionCommand().equals ("BUSY"))
frame.setCursor (busy);
else if (e.getActionCommand().equals ("DONE"))
frame.setCursor (done);
else if (e.getActionCommand().equals ("SLEEP"))
frame.setCursor (busy);
try { Thread.sleep (3000); } catch (Exception ex) { }
frame.setCursor (done);
System.out.print (" finished");
else if (e.getActionCommand().equals ("INVOKE LATER"))
frame.setCursor (busy);
SwingUtilities.invokeLater (thread);
else if (e.getActionCommand().equals ("DELAY"))
try { Thread.sleep (3000); } catch (Exception ex) { }
frame.setCursor (busy);
try { Thread.sleep (3000); } catch (Exception ex) { }
frame.setCursor (done);
System.out.print (" finished");
System.out.println();
Runnable thread = new Runnable()
public void run()
try { Thread.sleep (3000); } catch (Exception ex) { }
frame.setCursor (done);
System.out.println (" finished");
public static void main (String[] args)
BusyFrameTest f1 = new BusyFrameTest ("F1");
f1.addListeners (f1);
BusyFrameTest f2 = new BusyFrameTest ("F2");
BusyFrameTest f3 = new BusyFrameTest ("F3");
f2.addListeners (f3); // 2 listens to 3
f3.addListeners (f2); // 3 listens to 2

I've had the same problems with cursors and repaints in a swing application, and I was thinking of if I could use invokeLater, but I never got that far with it.
I still believe you would need a thread for the time consuming task, and that invokeLater is something you only need to use in a thread different from the event thread.

Can i call a JMenuBar in a number of JFrame(s) ?

Hi ,
I've a program with a number of JFrames.
I wanted to add a JMenuBar for each frame of my program, this menu bar has the same design code and the same events code in all the program frames, so is there a way to create this JMenuBar once only & call it some how in every JFrame to load it directly instead of writing its same code a lot of times for every JFrame ?
Thanks ,
Hesham

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
class Test{
     public static void main( String[] argv ) throws Throwable {
          for(int i=0; i<10; i++){
               SuperFrame f = new SuperFrame();
               f.setLocation(i*10,i*10);
               f.setSize(400,300);
               f.setVisible(true);
class SuperFrame extends JFrame{
     private static final long serialVersionUID = 1L;
      * All the menu item goes here
     JMenuBar mbar = new JMenuBar();
     JMenu menu = new JMenu("Menu");
     JMenuItem menuItem1 = new JMenuItem("Close");
     JMenuItem menuItem2 = new JMenuItem("Exit");
     public SuperFrame(){
          super("Testing");
          this.menu.add(menuItem1);
          this.menu.add(menuItem2);
          this.mbar.add(menu);
          this.setJMenuBar(mbar);
          menuItem1.addActionListener(new ActionListener(){
               @Override
               public void actionPerformed(ActionEvent arg0) {
                    dispose();
          menuItem2.addActionListener(new ActionListener(){
               @Override
               public void actionPerformed(ActionEvent arg0) {
                    System.exit(0);
}

Can't print JFrame

Hi,
i am trying to print out a JFrame that contains other Swing and AWT components, such as JTables and menus etc.
The problem is that the options that i select from the pageformat dialog, so not get set when the printing is taking place. As a result my jframe gets cut up into 4 differnet bits and each comes out on a seperate page. I cannot specify number of copies or size of paper either. Also once the ok button is pressed on the print dialogue, then the print dialogue comes back again and i have to press Ok, or Cancel to get rid of it. My code is below, please can someone suggest anything:
]public int print(Graphics g, PageFormat pf, int pi) throws PrinterException
          if (pi >= 1)
               return Printable.NO_SUCH_PAGE;
          Graphics2D g2 = (Graphics2D) g;
          g2.translate(pf.getImageableX(), pf.getImageableY());
          g2.setColor(Color.black);
          paint(g2);
          return Printable.PAGE_EXISTS;
PrinterJob pjob = PrinterJob.getPrinterJob();
PageFormat pf = pjob.defaultPage();
pjob.setPrintable(TransponderGraph.this, pf);
try
pjob.print();
catch (PrinterException e) { }

Just comment this line frame.setAlwaysOnTop(x);

Can not add a picture to the JFrame from an ActionListener class

As topic says, I can not add a picture to the JFrame from an ActionListener class which is a class inside the JFrame class.
I have a Map.java class where I load an image with ImageIcon chosen with JFileChooser.
I my window class (main class), I have following:
class OpenImage_Listener implements ActionListener
     public void actionPerformed(ActionEvent e)
          int ans = open.showOpenDialog(MainProgram.this);     // "open" is the JFileChooser reference
          if(ans == open.APPROVE_OPTION)
               File file = open.getSelectedFile();
               MainProgram.this.add(new Map(file.getName()), BorderLayout.CENTER);     // this line does not work - it does not add the choosen picture on the window,
                        //but if I add the picture outside this listener class and inside the MainProgram constructor, the picture apperas, but then I cannot use the JFileChooser.
                        showMessageDialog(MainProgram.this, fil.getName() ,"It works", INFORMATION_MESSAGE); // this popup works, and thereby the ActionListener also works.
}So why can�t I add a picture to the window from the above listener class?

The SSCCE:
Ok, I think I solved it with the picture, but now I cannot add new components after adding the picture.
Look at the comment in the actionlistener class:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.io.*;
public class Test extends JFrame{
     JButton b = new JButton("Open");
     JFileChooser jfc = new JFileChooser(System.getProperty("user.dir"));
     Picture pane;
     Test(){
          super("Main Program");
          setLayout(new BorderLayout());
          JPanel north = new JPanel();
          add(north, BorderLayout.NORTH);
          north.add(b);
          b.addActionListener(new Listener());
          setVisible(true);
          setSize(500,500);
          pane = new Picture("");
          add(pane, BorderLayout.CENTER);
     class Listener implements ActionListener {
          public void actionPerformed(ActionEvent e){
               int ans = jfc.showOpenDialog(Test.this);
               if(ans == jfc.APPROVE_OPTION)
                    File file = jfc.getSelectedFile();
                    Test.this.add(new Picture(file.getName()), BorderLayout.CENTER);
                    pane.add(new JButton("NEW BUTTON")); // Why does this button not appear on the window???
                    pane.repaint();
                    pane.revalidate();
     public static void main(String[] args)
          Test t = new Test();
class Picture extends JPanel
     Image pic;
     String filename;
     Picture(String filename)
          setLayout(null);
          this.filename = filename;
          pic = Toolkit.getDefaultToolkit().getImage(filename);
        protected void paintComponent(Graphics g)
            super.paintComponent(g);
            g.drawImage(pic,0,0,getWidth(),getHeight(),this);
            revalidate();
}

JFrame can not be visiable on WinXP.

I create a frame which extends from JFrame. when a button is clicked, the frame should be visiable. On Win 2000, it runs, but on Win Xp , it does not run, the frame does not appear. But the other frame which also extends from the JFrame runs on both system. The Java SDK is version 1.4.2.
Could anybody help me?
coral9527

Are the files you are trying to import mp3's? If not then either use iTunes to convert them or get some other third party program (i found a few really good ones but i can't remember what they were called). If they are mp3 maybe try converting them to mp3 again using a different encoder? (my LAME encoded ones seem to work fine)

JFrame

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