How to make a proper button listener?

[Avin Sinanan]

Hello I've created some code to do the following:
1)It creates a frame and a panel.
2)A background image is added to the panel.
3)The panel is then added to the frame.
4)Then a image ( a jpg) moves from one point to
another on the panel. It move in a continuous motion from one point to another.
Ok the code below does the above. It should be noted that the code belows works perfectly. Examine to code and then I'll tell you what I trie dto extend the code to do and the problem I encounterd.

import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
import java.util.*;
import java.awt.*;
import java.lang.Number.*;
class Test
{
public static void main(String[] args)
{
        Move move = new Move();
}
}

class Move
{
public JFrame frame ;
public ImagePnl pane ;
public JLabel label;
public Move()
{
frame = new JFrame();
pane = new ImagePnl();
pane.setLayout(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(800,770);
frame.setVisible(true);

JLabel van = new JLabel(new ImageIcon("VAN.jpg"));
for(int i=219 ; i <=412 ; i++ )
{
Calculation cal = new Calculation();
double x2minusx1 = 193 ;
int y = cal.calculation(219,359,412,344,i,x2minusx1);
van.setBounds(i,y,40,40);
pane.add(van);
frame.getContentPane().add(pane);
pane.updateUI();
}
    }
}
class ImagePnl extends JPanel
{
ImageIcon ic = new ImageIcon("GSMMAP2.jpg");
public ImagePnl()
{
}
public void paintComponent(Graphics g)
{
g.drawImage(ic.getImage() ,0,0,Color.red, null);
}


}

Ok note that was soon as the program is executed the small image ( VAN.jpg) starts to move in a smoothe motion (using the for loop) from one point to another.
However I do not want it to start right away. Instead I want to add a button to another frame and only when that button is pressed only then does the VAN.jpg image starts to move..only when that button is pressed. The code below is what I did to try to implement this. However when I ran the code below and the button was pressed the VAN.jpg picture moved to its final position and only then was it shown. That is - the user did not see the image move continously from one point to another. All the user sees is the image in its final position after the button was pressed.
Can someone tell me what am doing wrong. Thanks a million. Here is the code.

import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
import java.util.*;
import java.awt.*;
import java.lang.Number.*;
class Test
{
public static void main(String[] args)
{
        JFrame frame = new JFrame();
JPanel pane = new JPanel();
JButton button = new JButton("Hello");

button.addActionListener(new ActionListener(){
    public void actionPerformed(ActionEvent e){
            
          Move move = new Move();
         }
});
        pane.add(button);
        frame.getContentPane().add(pane);
        frame.setSize(100,100);
        frame.setVisible(true);
}
}

class Move
{
public JFrame frame ;
public ImagePnl pane ;
public JLabel label;
public Move()
{
frame = new JFrame();
pane = new ImagePnl();
pane.setLayout(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(800,770);
frame.setVisible(true);

JLabel van = new JLabel(new ImageIcon("VAN.jpg"));
for(int i=219 ; i <=412 ; i++ )
{
Calculation cal = new Calculation();
double x2minusx1 = 193 ;
int y = cal.calculation(219,359,412,344,i,x2minusx1);
van.setBounds(i,y,40,40);
pane.add(van);
frame.getContentPane().add(pane);
pane.updateUI();
}
    }
}
class ImagePnl extends JPanel
{
ImageIcon ic = new ImageIcon("GSMMAP2.jpg");
public ImagePnl()
{
}
public void paintComponent(Graphics g)
{
g.drawImage(ic.getImage() ,0,0,Color.red, null);
}


}

[Dirk Schreckmann]

Hello,
If you'd include all of the code (class Calculation is missing), I'd be glad to test it and let you know what I figure out. Otherwise, my guessing abilities are too limited at this hour.
Good Luck,
-Dirk Schreckmann

[Avin Sinanan]

Hello Dirk this is the missing Calculation class
..thanks again
Atually here is the full code again...

import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
import java.util.*;
import java.awt.*;
import java.lang.Number.*;
class Test
{
public static void main(String[] args)
{
        Move move = new Move();
}
}

class Move
{
public JFrame frame ;
public ImagePnl pane ;
public JLabel label;
public Move()
{
frame = new JFrame();
pane = new ImagePnl();
pane.setLayout(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(800,770);
frame.setVisible(true);

JLabel van = new JLabel(new ImageIcon("VAN.jpg"));
for(int i=219 ; i <=412 ; i++ )
{
Calculation cal = new Calculation();
double x2minusx1 = 193 ;
int y = cal.calculation(219,359,412,344,i,x2minusx1);
van.setBounds(i,y,40,40);
pane.add(van);
frame.getContentPane().add(pane);
pane.updateUI();
}
    }
}
class ImagePnl extends JPanel
{
ImageIcon ic = new ImageIcon("GSMMAP2.jpg");
public ImagePnl()
{
}
public void paintComponent(Graphics g)
{
g.drawImage(ic.getImage() ,0,0,Color.red, null);
}


}
class Calculation
{
private double  x1, x2,y1,y2 , no ;
private double i ;
public Calculation()
{
}

    public int calculation(double x1e , double y1e , double x2e , double y2e , int ie ,double noe)
{
x1 = x1e ;
y1 = y1e;
x2 = x1e ;
y2 = y2e ;
i  = ie ;
no = noe;




double m = (y2-y1)/no ;
double j = ( y1 - (m*x1) ) ;
int c ;
c = (int)j;
double z = (m*i + c) ;
int pop ;
pop = (int)z ;
return pop ;
}
}

[ March 11, 2002: Message edited by: Avin Sinanan ]

[Manfred Leonhardt]

Hi Avin,
You will need to make a new Thread to have your image move along. Change your Move class to the one below and enjoy.

class Move implements Runnable
{
  public JFrame frame ;
  public ImagePnl pane ;
  public JLabel van;
  
  public Move()
  {
    frame = new JFrame();
    pane = new ImagePnl();
    pane.setLayout(null);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.getContentPane().add(pane);
    frame.setSize(800,770);
    frame.setVisible(true);
    van = new JLabel( new ImageIcon("VAN.jpg") );
    pane.add(van);
    new Thread( this ).start();
  }
  public void run()
  {
    for(int i=219 ; i <=412 ; i++ )
    {
      Calculation cal = new Calculation();
      double x2minusx1 = 193 ;
      int y = cal.calculation( 219,359,412,344,i,x2minusx1 );
      van.setBounds( i,y,40,40 );
      pane.updateUI();
      try
      {
        Thread.sleep( 500 );
      }
      catch( InterruptedException e ) {}
    }    
  }
}

Regards,
Manfred.