Thread problem in swing application?

Question

Hi,
I have a doubt in GridLayout and Threads. I�m doing one small application which is accepting images and Alphabets. Actually, What I�m doing running images and alphabets(combinedly) in frequent intervals. For this I used GridLayout and Thread concept. But I have a problem in paint method. How to call the GridLayout frequently. In GridLayout , I�m putting Images and alphabets. Acutually in paint method , there are only drawString or drawImage or other methods. Is it possible to call my layout. Is so, can anybody help me in this regard. Is there any way to do it . please suggest me.
Thanks,
-Balaji
My code follows:
import java.awt.*;
import java.awt.event.*;
import java.awt.Graphics;
import java.awt.Color;
import javax.swing.*;
import java.applet.Applet;
import java.util.*;
import java.io.*;
public class GridLayEx2 extends Applet implements Runnable {
private Random r = new Random();
private Thread imageThread = null;
GridLayout glt;
public void init() {
glt = new GridLayout(3,3);
setLayout(glt);
} // end of init method
public void start(){
if (imageThread == null) {
imageThread = new Thread(this, "GridLayEx2");
imageThread.start();
} // end of start method
public void run(){
Thread myThread = Thread.currentThread();
while (imageThread == myThread) {
repaint();
try {
Thread.sleep(1000);
} catch (InterruptedException e){ }
}// end of run method
public void paint(Graphics g){
Font boldFont = new Font("Helvetica", Font.BOLD, 25);
Font plainDerived =
boldFont.deriveFont(Font.PLAIN, 25);
JLabel myLabel[] = new JLabel[9];
String myUrl = "C:\\Regoti\\Vision\\AP\\Project\\Version1\\images\\duke1.gif";
myLabel[0] = new JLabel(new ImageIcon(myUrl));
myLabel[1] = new JLabel("A");
myLabel[2] = new JLabel("A");
myLabel[3] = new JLabel("A");
myLabel[4] = new JLabel("A");
myLabel[5] = new JLabel("A");
myLabel[6] = new JLabel("A");
myLabel[7] = new JLabel("A");
myLabel[8] = new JLabel("A");
myLabel[1].setFont(boldFont);
myLabel[2].setFont(boldFont);
myLabel[3].setFont(boldFont);
myLabel[4].setFont(boldFont);
myLabel[5].setFont(boldFont);
myLabel[6].setFont(boldFont);
myLabel[7].setFont(boldFont);
myLabel[8].setFont(boldFont);
int values[] = new int[9];
values = gen_pos_uni_ran_num(0,8);
for(int i = 0; i < 9; i++)
add(myLabel[values]);
} // end of paint method
public void stop(){
imageThread = null;
} // end of stop method
public int[] gen_pos_uni_ran_num(int min, int max)
int results[] = new int[Math.abs(max - min) + 1];
for(int i = 0; i < results.length; ++i)
results = -1;
outer_loop:
for(int i = 0; i < results.length; ++i)
int random_int = (int)((Math.random() * results.length) + min);
for(int j = 0; j < results.length; ++j)
if(results[j] == random_int)
random_int = (int)((Math.random() * results.length) + min);
j = -1;
continue;
if(j == results.length - 1)
results = random_int;
continue outer_loop;
return results;
} // generate unique random numbers
public static void main( String args[])
Frame GridLayFrame = new Frame ( " Grid Layout Frame ");
GridLayEx2 gl = new GridLayEx2();
gl.init();
GridLayFrame.add(gl);
GridLayFrame.pack();
GridLayFrame.setSize(GridLayFrame.getPreferredSize());
GridLayFrame.show();
GridLayFrame.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
} // end of main method

Answer 1

hi,
i got one doubt in the previous application. i want to put labels in the circle manner while changing my label positions. Now it is rectangular type. And also i want to change my background color of JFrame. Please see my code ...
import java.awt.*;
import java.awt.event.*;
import java.awt.Graphics;
import java.awt.Color;
import javax.swing.*;
import java.util.*;
import java.io.*;
import java.net.URL;
import java.net.MalformedURLException;
import java.util.GregorianCalendar;
public class GridLayEx6 extends JApplet{ 
   private Random r = new Random(); 
   private ActionListener taskPerformer;
   private javax.swing.Timer timer;  
   private GridLayout glt;  
   private JLabel[] myLabel;     
   GregorianCalendar todayDate = new GregorianCalendar();     
   long fromTime,toTime,elapsedTime;
   public void init() {     
        glt = new GridLayout(3,3);     
      Font boldFont = new Font("Helvetica", Font.BOLD, 25);     
      Font plainDerived = boldFont.deriveFont(Font.PLAIN, 25);     
         myLabel = new JLabel[9];     
         String myUrl = "C:\\Regoti\\Vision\\AP\\Project\\Version1\\images\\MyArrow.jpg";
         String myUrlA = "C:\\Regoti\\Vision\\AP\\Project\\Version1\\images\\MyA.jpg";     
         URL url = null;     
   try{
   myLabel[0] = new JLabel(new ImageIcon(myUrl), SwingConstants.CENTER);     
   myLabel[1] = new JLabel(new ImageIcon(myUrl), SwingConstants.CENTER);
   myLabel[2] = new JLabel(new ImageIcon(myUrl), SwingConstants.CENTER);
   myLabel[3] = new JLabel(new ImageIcon(myUrl), SwingConstants.CENTER);
   myLabel[4] = new JLabel("+", SwingConstants.CENTER);     
   myLabel[5] = new JLabel(new ImageIcon(myUrlA), SwingConstants.CENTER);
   myLabel[6] = new JLabel(new ImageIcon(myUrl), SwingConstants.CENTER);
   myLabel[7] = new JLabel(new ImageIcon(myUrl), SwingConstants.CENTER);
   myLabel[8] = new JLabel(new ImageIcon(myUrl), SwingConstants.CENTER);
   myLabel[2].setVerticalAlignment(SwingConstants.NORTH);     
   myLabel[4].setFont(boldFont);     
   getContentPane().setLayout(glt);     
  } catch( Exception e)
    { System.out.println(" Exception occurs "+e);}
   int delay = 20000; //milliseconds     
   ActionListener taskPerformer = new ActionListener() {     
   public void actionPerformed(ActionEvent evt) {      
             randomDuke();
   timer = new javax.swing.Timer(delay, taskPerformer);     
   addKeyListener(new KeyAdapter()      {        
      public void keyPressed(KeyEvent e){           
             GridLayEx6 gl2 = (GridLayEx6)e.getSource();           
                 switch(e.getKeyCode())
                       case(KeyEvent.VK_ENTER): 
                            gl2.randomDuke();                 
                            break;
                   case(KeyEvent.VK_SPACE):              
                        if(gl2.timer.isRunning())                    
                          { gl2.timer.stop();                 
                                toTime = System.currentTimeMillis();
                             elapsedTime = toTime - fromTime;
                             System.out.println("toTime : "+toTime);
                             System.out.println("elapsedTime : "+elapsedTime);
                              gl2.timer.start();
                               gl2.randomDuke();
                           break;
                   case(KeyEvent.VK_KP_RIGHT):case(KeyEvent.VK_KP_UP):              
                   case(KeyEvent.VK_RIGHT):case(KeyEvent.VK_UP):              
                     int delay = gl2.timer.getDelay();
                     if(delay > 0)                    
                        gl2.timer.setDelay(delay - 100);                 
                        break;
                   case(KeyEvent.VK_KP_LEFT):case(KeyEvent.VK_KP_DOWN):              
                   case(KeyEvent.VK_LEFT):case(KeyEvent.VK_DOWN):
                        int delay = gl2.timer.getDelay();                  
                        if(delay < 10000)                    
                             gl2.timer.setDelay(delay + 100);                  
                             break;
                   //timer.start();  
         } // end of init method  
         public void start()   {     
              timer.start();     
                while(!isFocusOwner())        
                        requestFocus(); 
         } // end of start method     
         public void stop(){    
              timer.stop();
        } // end of stop method     
         /** To make sure we have focus in application *  
         * mode if JFrame loses focus control          *  
         * - non standard usage of paintComponent      */    
         public void paintComponent(Graphics g)   {
              while(!isFocusOwner())        
                   requestFocus();  
        public void randomDuke()   {     
              fromTime = System.currentTimeMillis();
              System.out.println("fromtime : "+fromTime);     
              getContentPane().removeAll();     
              int[] values = new int[9];     
              int temp;
              values = gen_pos_uni_ran_num(0,8);     
              for ( int i=0; i<=8;i++)
                      if ( values[i] == 4)
                             temp = 4;
                             values[i] = values[4];
                             values[4] = temp;
              for(int q = 0; q < 9; q++)   
                    getContentPane().add(myLabel[values[q]]);    
                   myLabel[0].revalidate();
                   myLabel[1].revalidate();
                   myLabel[2].revalidate();
                   myLabel[3].revalidate();
                   myLabel[5].revalidate();
                   myLabel[6].revalidate();
                   myLabel[7].revalidate();
                   myLabel[8].revalidate();
                } // end of randomDuke method  
          public int[] gen_pos_uni_ran_num(int min, int max)   {     
              int results[] = new int[Math.abs(max - min) + 1];     
              for(int q = 0; q < results.length; ++q) 
                   results[q] = -1;     
              outer_loop:     
              for(int q = 0; q < results.length; ++q)  
                   int random_int = (int)((Math.random() * results.length) + min);        
                for(int j = 0; j < results.length; ++j)       
                    if(results[j] == random_int)            {              
                        random_int = (int)((Math.random() * results.length) + min);              
                        j = -1;
                  continue;           
                 if(j == results.length - 1)
                      results[q] = random_int;              
                      continue outer_loop;
              return results;  
              } // generate unique random numbers  
              public static void main( String args[])
                    JFrame GridLayFrame = new JFrame ( " Grid Layout Frame ");     
                   GridLayFrame.setSize(500,500);     
                   GridLayEx6 gl = new GridLayEx6();     
                   gl.init();     
                   GridLayFrame.getContentPane().add(gl);     
                   //GridLayFrame.setBackgroundColor(Color.white);
                   GridLayFrame.setVisible(true);
                   gl.start();     
                   GridLayFrame.addWindowListener(new WindowAdapter()      
                     public void windowClosing(WindowEvent e)         
                    System.exit(0);         }      });  
              } // end of main method
              }