Java Applet JOptionPane and setSize issue

Question

I'll start by saying that I'm a bit new to java, so if it's a stupid mistake, that's the reason.

I was messing with applets in java, and I've run into a problem when setting the size of the window, and using JOptionPane, whether it's just showing a message, or getting input through it, it displays three or more panes, rather than simply one. I'm on Ubuntu 12.04(x64), and here is my test code that still encounters the problem:

import javax.swing.JOptionPane;
import java.awt.Graphics;
import java.applet.Applet;

public class Main extends Applet{

    public void paint(Graphics g)
    {
        //setup screen size
        setSize((int)500,(int)500);
        //print test message
        JOptionPane.showMessageDialog(null, "There Should Be One Of Me!");
    }
}

That's expected: there are as many option panes as number of calls to the paint method :-) the latter is not controllable by application code, neither in AWT nor in Swing. Never-ever change any component state in methods called during the paint cycle. — kleopatra, Jul 08 '12 at 09:54
Ok, thats the answer I was looking for, if you could put that in an answer, that would be great... — John, Jul 08 '12 at 17:59
*"I was messing with applets in java, and I've run into a problem when setting the size of the window"* That will not work reliably in the web page. Abandon it and try something useful. And use a `JApplet`. Either that or make it a `JFrame` and launch the frame from a link using [JWS](http://stackoverflow.com/tags/java-web-start/info). — Andrew Thompson, Jul 09 '12 at 12:29

score 2 · Accepted Answer · answered Jul 08 '12 at 18:07

That's expected: there are as many option panes as number of calls to the paint method :-) the latter is not controllable by application code, neither in AWT nor in Swing.

As a general rule, never-ever change any component state in methods called during the paint cycle

score 0 · Answer 2 · answered Jul 07 '12 at 18:14

0

remove setSize(.. and JOptionPane.sh... from public void paint(Graphics g)
for Applet I miss there method init()
(J)Applet tutorial shows a few examples
maybe better could be to use Swing JFrame instead of (J)Applet

answered Jul 07 '12 at 18:14

mKorbel

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For reference, there's a hybrid applet/application [here](http://stackoverflow.com/a/11372932/230513). – trashgod Jul 07 '12 at 18:38
not sure what's wrong, maybe temperature in the Central Europe ???, hmmm but I love > 32 degrees by Celsius to much – mKorbel Jul 08 '12 at 11:42
aaaach I seeeeeeeee too much links to the external sites :-) – mKorbel Jul 08 '12 at 12:03
no, too many (all except the first) unrelated bullets. Still trying to nudge you into staying focused on the problem at hand instead of mentioning whatever comes to your mind :-) – kleopatra Jul 08 '12 at 18:11

Java Applet JOptionPane and setSize issue

2 Answers2