Develop Reference

How to download and display an image with SwingWorker [duplicate]

I want to display an image from the web to a panel in another JFrame at the click of a button. Whenever I click the button, first the image loads; and during this time, the current form potentially freezes. Once the image has loaded, the form is displayed with the image. How can I avoid the situation where my form freezes since it is very irritating. Among my codes:
My current class:
private void btn_TrackbusActionPerformed(java.awt.event.ActionEvent evt) {
try {
sendMessage("Query,map,$,start,211,Arsenal,!");
System.out.println(receiveMessage());
} catch (UnknownHostException ex) {
Logger.getLogger(client_Trackbus.class.getName()).log(Level.SEVERE, null, ex);
} catch (IOException ex) {
Logger.getLogger(client_Trackbus.class.getName()).log(Level.SEVERE, null, ex);
}
catch (Exception ex) {
Logger.getLogger(client_Trackbus.class.getName()).log(Level.SEVERE, null, ex);
}
client_trackedbus nextform=new client_trackedbus(planform,connection,packet_receive,packet_send);
this.setVisible(false);
this.dispose();
nextform.setVisible(true);
// TODO add your handling code here:
}
My next class that displays the image:
public class client_trackedbus extends javax.swing.JFrame {
client_planform planform=null;
DatagramSocket connection=null;
DatagramPacket packet_receive=null;
DatagramPacket packet_send=null;
JLabel label=null;
/** Creates new form client_trackedbus */
public client_trackedbus(client_planform planform,DatagramSocket connection,DatagramPacket packet_receive,DatagramPacket packet_send) {
initComponents();
this.planform=planform;
this.connection=connection;
this.packet_receive=packet_receive;
this.packet_send=packet_send;
try {
displayMap("http://www.huddletogether.com/projects/lightbox2/images/image-2.jpg", jPanel1, new JLabel());
} catch (MalformedURLException ex) {
Logger.getLogger(client_trackedbus.class.getName()).log(Level.SEVERE, null, ex);
}
}
private void displayMap(String url,JPanel panel,JLabel label) throws MalformedURLException{
URL imageurl=new URL(url);
Image image=(Toolkit.getDefaultToolkit().createImage(imageurl));
ImageIcon icon = new ImageIcon(image);
label.setIcon(icon);
panel.add(label);
// System.out.println(panel.getSize().width);
this.getContentPane().add(panel);
}
/** This method is called from within the constructor to
* initialize the form.
* WARNING: Do NOT modify this code. The content of this method is
* always regenerated by the Form Editor.
*/
#SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jPanel1 = new javax.swing.JPanel();
jLabel1 = new javax.swing.JLabel();
btn_Exit = new javax.swing.JButton();
btn_Plan = new javax.swing.JButton();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
setTitle("Public Transport Journey Planner");
javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1);
jPanel1.setLayout(jPanel1Layout);
jPanel1Layout.setHorizontalGroup(
jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGap(0, 368, Short.MAX_VALUE)
);
jPanel1Layout.setVerticalGroup(
jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGap(0, 172, Short.MAX_VALUE)
);
jLabel1.setFont(new java.awt.Font("Arial", 1, 18));
jLabel1.setText("Your tracked bus");
btn_Exit.setText("Exit");
btn_Exit.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
btn_ExitActionPerformed(evt);
}
});
btn_Plan.setText("Plan journey");
btn_Plan.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
btn_PlanActionPerformed(evt);
}
});
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(104, 104, 104)
.addComponent(jLabel1))
.addGroup(layout.createSequentialGroup()
.addContainerGap()
.addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGroup(layout.createSequentialGroup()
.addGap(65, 65, 65)
.addComponent(btn_Plan)
.addGap(65, 65, 65)
.addComponent(btn_Exit, javax.swing.GroupLayout.PREFERRED_SIZE, 87, javax.swing.GroupLayout.PREFERRED_SIZE)))
.addContainerGap(20, Short.MAX_VALUE))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(35, 35, 35)
.addComponent(jLabel1)
.addGap(18, 18, 18)
.addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(18, 18, 18)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(btn_Exit)
.addComponent(btn_Plan))
.addContainerGap(12, Short.MAX_VALUE))
);
pack();
}// </editor-fold>
private void btn_ExitActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
Exitform();
}
private void btn_PlanActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
this.setVisible(false);
this.dispose();
this.planform.setVisible(true);
}
private void Exitform(){
this.setVisible(false);
this.dispose();
}
/**
* #param args the command line arguments
*/
public static void main(String args[]) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
// new client_trackedbus().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JButton btn_Exit;
private javax.swing.JButton btn_Plan;
private javax.swing.JLabel jLabel1;
private javax.swing.JPanel jPanel1;
// End of variables declaration
}

As suggested in the article Concurrency in Swing, your button handler's query may be blocking the event dispatch thread. Using javax.swing.SwingWorker is one approach to loading images in the background, while displaying progress and keeping the GUI thread alive.
Addendum: Here's a sscce that loads the SO logo; it's been updated to handle exceptions and resize the enclosing container to fit the loaded image:
import java.awt.*;
import java.io.IOException;
import java.net.URL;
import java.util.concurrent.ExecutionException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.imageio.ImageIO;
import javax.swing.*;
/**
* #see http://stackoverflow.com/questions/4530659
*/
public final class WorkerTest extends JFrame {
private final JLabel label = new JLabel("Loading...");
public WorkerTest() {
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
label.setHorizontalTextPosition(JLabel.CENTER);
label.setVerticalTextPosition(JLabel.BOTTOM);
this.add(label);
this.pack();
this.setLocationRelativeTo(null);
}
private void start() {
new ImageWorker().execute();
}
public static void main(String args[]) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
WorkerTest wt = new WorkerTest();
wt.setVisible(true);
wt.start();
}
});
}
class ImageWorker extends SwingWorker<Image, Void> {
private static final String TEST
= "http://cdn.sstatic.net/stackexchange/img/logos/so/so-logo.png";
#Override
protected Image doInBackground() throws IOException {
Image image = ImageIO.read(new URL(TEST));
return image.getScaledInstance(640, -1, Image.SCALE_SMOOTH);
}
#Override
protected void done() {
try {
ImageIcon icon = new ImageIcon(get());
label.setIcon(icon);
label.setText("Done");
WorkerTest.this.pack();
WorkerTest.this.setLocationRelativeTo(null);
} catch (InterruptedException | ExecutionException e) {
e.printStackTrace();
}
}
}
}

public class SSBTest extends javax.swing.JFrame {
/** Creates new form worker1 */
public SSBTest() {
initComponents();
}
/** This method is called from within the constructor to
* initialize the form.
* WARNING: Do NOT modify this code. The content of this method is
* always regenerated by the Form Editor.
*/
#SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jLabel1 = new javax.swing.JLabel();
jPanel1 = new javax.swing.JPanel();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
jLabel1.setText("jLabel1");
javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1);
jPanel1.setLayout(jPanel1Layout);
jPanel1Layout.setHorizontalGroup(
jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING).addGap(0, 348, Short.MAX_VALUE));
jPanel1Layout.setVerticalGroup(
jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING).addGap(0, 210, Short.MAX_VALUE));
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING).addGroup(layout.createSequentialGroup().addContainerGap(196, Short.MAX_VALUE).addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 182, javax.swing.GroupLayout.PREFERRED_SIZE).addGap(178, 178, 178)).addGroup(layout.createSequentialGroup().addGap(86, 86, 86).addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE).addContainerGap(122, Short.MAX_VALUE)));
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING).addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup().addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE).addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 40, Short.MAX_VALUE).addComponent(jLabel1).addGap(36, 36, 36)));
pack();
}// </editor-fold>
/**
* #param args the command line arguments
*/
public static void main(String args[]) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
final SSBTest ssbTest = new SSBTest();
ssbTest.setVisible(true);
ssbTest.execute();
}
});
}
private void execute() {
(new MeaningOfLifeFinder(jLabel1, jPanel1)).execute();
}
// Variables declaration - do not modify
private javax.swing.JLabel jLabel1;
private javax.swing.JPanel jPanel1;
// End of variables declaration
}
class MeaningOfLifeFinder extends SwingWorker<Icon, Object> {
JLabel label = null;
JPanel panel;
MeaningOfLifeFinder(JLabel label, JPanel jpanel) {
this.label = label;
this.panel = jpanel;
}
protected Icon doInBackground() throws IOException {
URL imageurl;
Image image = null;
System.out.println("image loading");
imageurl = new URL("http://maps.google.com/maps/api/staticmap"
+ "?zoom=14&size=512x512&maptype=roadmap"
+ "&markers=color:green|label:21|-15.0,-150.0&sensor=false");
//image = (Toolkit.getDefaultToolkit().createImage(imageurl));
image = ImageIO.read(imageurl);
ImageIcon icon = new ImageIcon(image);
System.out.println("image loaded...");
return icon;
}
#Override
protected void done() {
try {
System.out.println("image adding to label...");
label.setIcon(get());
//panel.add(label);
System.out.println("image loaded to label...");
} catch (Exception ignore) {
}
}
// System.out.println(panel.getSize().width);
}

Error in splash screen in Java/Swing

I am creating new Splash screen in Java (using Netbeans as my IDE).
But the problem is that after reaching 100% by progress bar it is automatically move to 2nd frame and exit the 1st frame which is showing the splash screen. But here 1st screen of splash screen is not exiting.
This is my code
public NewJFrame() {
initComponents();
try {
for (int i=0;i<=100;i++){
Thread.sleep(40);
jLabel1.setText(Integer.toString(i)+"%");
jProgressBar2.setValue(i);
if (i==100)
{
this.setVisible(false);
new NewJFrame1().setVisible(true);
}
}
} catch (Exception e) {
}
}

I once created a simple splash, not to fancy but for me it did the trick.
This is a copy paste from the entire class from netbeans, so you will need to change somethings.
This example you will get a splash with a image and a progress bar bellow.
import javax.swing.SwingUtilities;
public class Splash extends javax.swing.JWindow {
private static final long serialVersionUID = -6711792976773608816L;
/**
* Creates new form Splash
*/
public Splash() {
initComponents();
}
public void splashScreenInit() {
setLocationRelativeTo(null);
setProgressMax(100);
setVisible(true);
}
/**
* This method is called from within the constructor to initialize the form. WARNING: Do NOT modify this code. The content of this method is always
* regenerated by the Form Editor.
*/
#SuppressWarnings("all")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
imageLabel = new javax.swing.JLabel();
progressBar = new javax.swing.JProgressBar();
imageLabel.setIcon(new javax.swing.ImageIcon(getClass().getResource("/images/help/splash.png"))); // NOI18N
getContentPane().add(imageLabel, java.awt.BorderLayout.CENTER);
progressBar.setForeground(new java.awt.Color(51, 85, 112));
progressBar.setStringPainted(true);
getContentPane().add(progressBar, java.awt.BorderLayout.PAGE_END);
pack();
}// </editor-fold>
/**
* Sets the max value for the progressbar
* #param maxProgress
*/
public void setProgressMax(int maxProgress) {
progressBar.setMaximum(maxProgress);
}
public void setProgress(int progress) {
final int theProgress = progress;
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
progressBar.setValue(theProgress);
}
});
}
/**
* Changes the string message and set a new value fro the progressbar
* #param message String the message
* #param progress int the new value of the progressbar. This cant be higher than the value defined in the setProgressMax
*/
public void setProgress(String message, int progress) {
final int theProgress = progress;
final String theMessage = message;
setProgress(progress);
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
progressBar.setValue(theProgress);
setMessage(theMessage);
}
});
}
private void setMessage(String message) {
if (message == null) {
message = "";
progressBar.setStringPainted(false);
} else {
progressBar.setStringPainted(true);
}
progressBar.setString(message);
}
// Variables declaration - do not modify
private javax.swing.JLabel imageLabel;
private javax.swing.JProgressBar progressBar;
// End of variables declaration
}
To call
final Splash s = new Splash();
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
s.splashScreenInit();
}
});
and in the end
s.setVisible(false);

the following is my code it is working properly in my system.. u can try add import the following in your codes
//import com.sun.awt.AWTUtilities;
//import java.awt.event.ActionEvent;
//import javax.swing.Timer;
//import javax.swing.UIManager;
//import java.awt.event.ActionListener;
//import javax.swing.JProgressBar;
private Timer t;
private ActionListener al;
/**
* Creates new form NewJFrame
*/
public NewJFrame() {
ActionListener a1 = new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
// throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
if(jProgressBar1.getValue()<100)
{
jProgressBar1.setValue(jProgressBar1.getValue()+5);
}
else
{
t.stop();
abcd();
}
}
};
t=new Timer(80, a1);
initComponents();
AWTUtilities.setWindowOpaque(this, false);
t.start();
}
#SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jPanel1 = new javax.swing.JPanel();
jLabel1 = new javax.swing.JLabel();
jProgressBar1 = new javax.swing.JProgressBar();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
setUndecorated(true);
jLabel1.setText("jLabel1");
javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1);
jPanel1.setLayout(jPanel1Layout);
jPanel1Layout.setHorizontalGroup(
jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(jPanel1Layout.createSequentialGroup()
.addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(jPanel1Layout.createSequentialGroup()
.addGap(123, 123, 123)
.addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 136, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGroup(jPanel1Layout.createSequentialGroup()
.addGap(92, 92, 92)
.addComponent(jProgressBar1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)))
.addContainerGap(141, Short.MAX_VALUE))
);
jPanel1Layout.setVerticalGroup(
jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(jPanel1Layout.createSequentialGroup()
.addGap(66, 66, 66)
.addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 46, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(41, 41, 41)
.addComponent(jProgressBar1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addContainerGap(133, Short.MAX_VALUE))
);
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jPanel1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jPanel1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
);
pack();
}// </editor-fold>
private void abcd()
{
NewJFrame1 f1= new NewJFrame1();
f1.setLocationRelativeTo(null);
f1.setVisible(true);
this.dispose();
}

How do I pass values between cards in Java CardLayout....this time i have given a good example

This is a simple code to clarify my question:
this is the main class from where I declared the two panels.
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
/**
*
* #author sakib
*/
public class MainPane {
private JPanel contentPane;
private Firstcard1 p1;
private SecondCard1 p2;
public void displayGUI()
{
JFrame frame = new JFrame("Card Layout Example");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel contentPane = new JPanel();
//a=S1;
contentPane.setLayout(new CardLayout());
p1 = new Firstcard1(contentPane);
p2 = new SecondCard1(contentPane);
contentPane.add(p1, "Panel 1");
contentPane.add(p2, "Panel 2");
frame.setContentPane(contentPane);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args)
{
SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
new MainPane().displayGUI();
}
}
);
}
}
this is the first card:
public class Firstcard1 extends javax.swing.JPanel {
private JPanel contentpane;
/**
* Creates new form Firstcard1
*/
public Firstcard1(JPanel cp) {
this.contentpane=cp;
initComponents();
}
/**
* This method is called from within the constructor to initialize the form.
* WARNING: Do NOT modify this code. The content of this method is always
* regenerated by the Form Editor.
*/
#SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jTextField1 = new javax.swing.JTextField();
Login = new javax.swing.JButton();
Login.setText("Login");
Login.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
LoginActionPerformed(evt);
}
});
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(this);
this.setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(117, 117, 117)
.addComponent(jTextField1, javax.swing.GroupLayout.PREFERRED_SIZE, 138, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGroup(layout.createSequentialGroup()
.addGap(158, 158, 158)
.addComponent(Login)))
.addContainerGap(145, Short.MAX_VALUE))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(105, 105, 105)
.addComponent(jTextField1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(18, 18, 18)
.addComponent(Login)
.addContainerGap(134, Short.MAX_VALUE))
);
}// </editor-fold>
private void LoginActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
CardLayout layout = (CardLayout)contentpane.getLayout();
layout.show(contentpane, "Panel 2");
}
// Variables declaration - do not modify
private javax.swing.JButton Login;
private javax.swing.JTextField jTextField1;
// End of variables declaration
}
this is the second card:
public class SecondCard1 extends javax.swing.JPanel {
private JPanel contentpane;
/**
* Creates new form SecondCard1
*/
public SecondCard1(JPanel cp) {
this.contentpane=cp;
initComponents();
}
/**
* This method is called from within the constructor to initialize the form.
* WARNING: Do NOT modify this code. The content of this method is always
* regenerated by the Form Editor.
*/
#SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jTextField1 = new javax.swing.JTextField();
back = new javax.swing.JButton();
back.setText("Back");
back.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
backActionPerformed(evt);
}
});
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(this);
this.setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(127, 127, 127)
.addComponent(jTextField1, javax.swing.GroupLayout.PREFERRED_SIZE, 136, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGroup(layout.createSequentialGroup()
.addGap(157, 157, 157)
.addComponent(back)))
.addContainerGap(137, Short.MAX_VALUE))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(121, 121, 121)
.addComponent(jTextField1, javax.swing.GroupLayout.PREFERRED_SIZE, 36, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(18, 18, 18)
.addComponent(back)
.addContainerGap(102, Short.MAX_VALUE))
);
}// </editor-fold>
private void backActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
CardLayout layout = (CardLayout)contentpane.getLayout();
layout.show(contentpane, "Panel 1");
}
// Variables declaration - do not modify
private javax.swing.JButton back;
private javax.swing.JTextField jTextField1;
// End of variables declaration
}
My question is.if I put a value in the textarea of the first card and press the login button.the value will appear in the text area of the second card.how can i do it?

You somehow have to pass a reference of the second panel to the first one:
Main class:
public class MainPane
{
public void displayGUI()
{
....
p1 = new Firstcard1(contentPane);
p2 = new SecondCard1(contentPane);
p1.setSecondCard(p2);
....
}
}
First card:
public class Firstcard1 extends javax.swing.JPanel {
....
private SecondCard secondCard;
void setSecondCard(SecondCard secondCard)
{
this.secondCard = secondCard;
}
....
private void LoginActionPerformed(java.awt.event.ActionEvent evt)
{
CardLayout layout = (CardLayout)contentpane.getLayout();
layout.show(contentpane, "Panel 2");
secondCard.getTextField().setText(jTextField1.getText());
}
}
Second card:
public class SecondCard1 extends javax.swing.JPanel
{
...
JTextField getTextField()
{
return jTextField1;
}
...
}
But when you continue like this, the program will probably become a mess pretty soon. I'd recommend to create these components manually, without using any visual GUI builders.

Progress Monitor Implementation in Java

I want to show the progress of my program process which using progress monitor in java. i've put this code below as progress monitor in my new frame.
package eksim.view;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JFrame;
import javax.swing.ProgressMonitor;
import javax.swing.SwingUtilities;
import javax.swing.Timer;
import javax.swing.UIManager;
public class ProgBar extends javax.swing.JInternalFrame implements ActionListener {
static ProgressMonitor pbar;
static int counter = 0;
/**
* Creates new form ProgBar
*/
public ProgBar() {
initComponents();
}
public void ProgressMonitorExample() {
super("Progress Monitor Demo");
setSize(250, 100);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
pbar = new ProgressMonitor(null, "Monitoring Progress",
"Initializing . . .", 0, 100);
// Fire a timer every once in a while to update the progress.
Timer timer = new Timer(500, this);
timer.start();
setVisible(true);
}
public static void main(String args[]) {
UIManager.put("ProgressMonitor.progressText", "This is progress?");
UIManager.put("OptionPane.cancelButtonText", "Go Away");
ProgressMonitorExample();
}
public void actionPerformed(ActionEvent e) {
// Invoked by the timer every half second. Simply place
// the progress monitor update on the event queue.
SwingUtilities.invokeLater(new Update());
}
class Update implements Runnable {
public void run() {
if (pbar.isCanceled()) {
pbar.close();
System.exit(1);
}
pbar.setProgress(counter);
pbar.setNote("Operation is " + counter + "% complete");
counter += 2;
}
}
/**
* This method is called from within the constructor to initialize the form.
* WARNING: Do NOT modify this code. The content of this method is always
* regenerated by the Form Editor.
*/
#SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jProgressBar1 = new javax.swing.JProgressBar();
setClosable(true);
setIconifiable(true);
setMaximizable(true);
setTitle("Progress Monitor");
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(31, 31, 31)
.addComponent(jProgressBar1, javax.swing.GroupLayout.PREFERRED_SIZE, 335, javax.swing.GroupLayout.PREFERRED_SIZE)
.addContainerGap(28, Short.MAX_VALUE))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
.addContainerGap(66, Short.MAX_VALUE)
.addComponent(jProgressBar1, javax.swing.GroupLayout.PREFERRED_SIZE, 27, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(48, 48, 48))
);
pack();
}// </editor-fold>
// Variables declaration - do not modify
private javax.swing.JProgressBar jProgressBar1;
// End of variables declaration
}
But, it didn't show anything as it works. Could anyone help me? Thanks

Apart from a few compilation problems in your code (detailed below), it works fine here. The progress bar updates as expected here.
First, move the code from public void ProgressMonitorExample() to the constructor, and remove that method. The constructor should look like this:
public ProgBar() {
super("Progress Monitor Demo");
initComponents();
setSize(250, 100);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
pbar = new ProgressMonitor(null, "Monitoring Progress",
"Initializing . . .", 0, 100);
// Fire a timer every once in a while to update the progress.
Timer timer = new Timer(500, this);
timer.start();
setVisible(true);
}
Second, since public void ProgressMonitorExample() is now gone, properly create a new ProgBar object instead:
public static void main(String args[]) {
UIManager.put("ProgressMonitor.progressText", "This is progress?");
UIManager.put("OptionPane.cancelButtonText", "Go Away");
ProgBar pb = new ProgBar();
}

Java Class to execute in JButton MouseClicked

I am new to Java. With this class I can open a pdf file:
public class ViewPdf {
public static void main(String[] args) throws Exception {
Process p =
Runtime.getRuntime()
.exec("rundll32 url.dll,FileProtocolHandler c:/pdf/mypdf.pdf");
p.waitFor();
System.out.println("Done.");
}
}
Now a want to use a Jbutton mouse event to fire this class and open that pdf. I'm working in Netbeans can someone give me some help?
NewJFrame.java
public class NewJFrame extends javax.swing.JFrame {
/** Creates new form NewJFrame */
public NewJFrame() {
initComponents();
}
/** This method is called from within the constructor to
* initialize the form.
* WARNING: Do NOT modify this code. The content of this method is
* always regenerated by the Form Editor.
*/
#SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jButton1 = new javax.swing.JButton();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
jButton1.setText("jButton1");
jButton1.addMouseListener(new java.awt.event.MouseAdapter() {
public void mouseClicked(java.awt.event.MouseEvent evt) {
jButton1MouseClicked(evt);
}
});
javax.swing.GroupLayout layout =
new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING,
layout.createSequentialGroup()
.addContainerGap(217, Short.MAX_VALUE)
.addComponent(jButton1)
.addGap(108, 108, 108))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(67, 67, 67)
.addComponent(jButton1)
.addContainerGap(210, Short.MAX_VALUE))
);
pack();
}// </editor-fold>
private void jButton1MouseClicked(java.awt.event.MouseEvent evt) {
// TODO add your handling code here:
}
/**
* #param args the command line arguments
*/
public static void main(String args[]) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new NewJFrame().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JButton jButton1;
// End of variables declaration
}
Thanks in advance...^^

As an alternative, you may be able to use open() in your button handler.

The place where you have
// TODO add your handling code here:
You can simply add your code to execute the PDF open
Process p = Runtime.getRuntime().exec("rundll32 url.dll,FileProtocolHandler c:/pdf/mypdf.pdf"); p.waitFor(); System.out.println("Done.");