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Rohit Gupta · Guest

I am having a JFrame which constitutes of a JComponent and a panel.
The JComponent is a separate class and the contents it displays is from
a variable in its class.
The problem is that when I change the values of that particular
varibale the JFrame isn't changed , means it still displays the
original diagram. However when I maximize it, I get now 2 JFrames one -
the original small size and another second - maximized one with the
modified values from the field behind the first one (which I am able to
see because I have written the pan function).
I have tried the following methods vaildate(), invalidate(), repaint(),
pack().
Can anyone tell me where does the problem lie and how could I manage to
fix that. Since I am short on time, I couldn't write a short self
compilable code because it would take some time.
I figure validate, invalidate fucntions don't work because I am not
adding or removing any particular component or maybe I am somewhere
wrong in using it. Could someone please elaborate on this.
An early reply would be highly appreciated.

TIA

Rohit

Rohit Gupta · Guest

I am updating that field using an update function since it doesnt pass
by value. Also I displayed that value to check wheher it is getting
updated or not. So no problem regarding that side.
Maybe my program has some intrinsic bugs, I shall try to preapre the
SSCCE and post soon. If you could give me some other lines of thougt
that would certainly help!

Rohit

hiwa · Guest

Java does pass-by-value for passing method arguments.
So, even if you re-assigned the caller reference, the callee
reference doesn't refer newly assigned object.

You need setXxx() method or something similar to update
the object referred by the callee reference.

However, I feel your code has its intrinsic bug(s).
Post a small demo code that is generally compilable,
runnable and could reproduce your problem. See:
http://homepage1.nifty.com/algafield/sscce.html

Thomas Weidenfeller · Guest

Rohit Gupta wrote:

Rohit Gupta · Guest

Ok, finally I have made the SSCCE, you can try it now and tell me what
is the problem...

What I am doing in this piece of code is that I am displaying initially
a button with text "start", on pressing the reload button the text
should alternately change from "dony" and "pony", try maximizing the
applet to see the problem.
Can anyone tell me now what to do.

I am in desperate need of help!!

TIA

Rohit

/*Launch.java*/

package javaapplication1;

public class Launch {

public static void main(String args[]){

Viewer view = new Viewer("start");
view.displayFrame();
view.displayResults();
}
}

/*Viewer.java*/

package javaapplication1;

import javax.swing.JFrame;
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.Button;
import java.awt.Panel;
import java.awt.Frame;

class Viewer implements ActionListener {

private String str;
private Button reload;
private JFrame mainFrame;
private Jbit jc;
boolean flag = true;

public Viewer (String str) {
this.str = str;
}

public void displayFrame() {

mainFrame = new JFrame("MODEL VIEWER");
mainFrame.setLocation(200, 100);
mainFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public void updateModel(String str) {

this.str = str;
}
public void displayResults () {

jc = new Jbit(str);
mainFrame.getContentPane().setLayout(new BorderLayout());
mainFrame.getContentPane().add("Center", jc);

reload = new Button("Reload");
reload.addActionListener(this);
Panel p = new Panel();
p.add(reload);
mainFrame.getContentPane().add("South", p);

mainFrame.pack();
mainFrame.setSize(600,600);
mainFrame.setVisible(true);

//Default view
}

public void refreshResults(String str) {

jc = new Jbit(str);
mainFrame.setSize(mainFrame.getSize().width,
mainFrame.getSize().height);
mainFrame.getContentPane().add("Center", jc);
mainFrame.invalidate();
mainFrame.validate();
mainFrame.setVisible(true);
}

public void actionPerformed(ActionEvent ae) {
String cmd = ae.getActionCommand();
if (cmd.equals("Reload")) {
if(flag){
refreshResults("pony");
flag = false;
}
else {
refreshResults("dony");
flag = true;
}
jc.validate();
}

}

}

/*Jbit.java*/

package javaapplication1;

import java.applet.Applet;
import java.awt.Button;
import java.awt.BorderLayout;

public class Jbit extends Applet {

private String str;
private Button button1;

//Applet started with a model
public Jbit (String str) {
this.str = str;
init();
}

public void init() {
setLayout(new BorderLayout());
button1 = new Button(str);
add(button1);
}

public void start () {

repaint();
}

public String getString () {

return str;

}
}

Oliver Wong · Guest

"Rohit Gupta" <rg.iitk (AT) gmail (DOT) com> wrote in message
news:1148291381.164115.202880 (AT) i39g2000cwa (DOT) googlegroups.com...