onClose()

Hi,
I know this has been explained at length before but I don't get it ! I have a JFrame, and when it is created and initialised, I set

Then, for the window Closing event, I have a JOptionPane ConfirmDialog box pop up which asks the user if they want to save before closing.
Whichever option they choose .... it closes ! It should NEVER close ... any ideas ?
Cheers,
Kate

HI,
You told the Frame to <b>do nothing</b> on closing NOT <b>not to close</b>!
As far as I know you cannot stop a top-level container from closing.
You could assign an OptionPane to the windowClosing(WindowEvent e) event - which is generated before it dissappears and then allow the user to cancel - though you'd have to capture the close event and consume it or something similar.
You can configure a JInternalFrame as not closable.
Hope that helps,

It works with JFrame... at least for me...

import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
 
public class NoCloseFrame extends JFrame {
    public static void main( String[] arg ) {
        new NoCloseFrame();
    }
 
    public NoCloseFrame() {
        super( "No Close Frame!" );
        setDefaultCloseOperation( DO_NOTHING_ON_CLOSE );
        setSize( 300, 300 );
        setVisible( true );
        addWindowListener( new AreYouSure() );
    }
 
    private class AreYouSure extends WindowAdapter {
        public void windowClosing( WindowEvent e ) {
            int option = JOptionPane.showOptionDialog(
                    NoCloseFrame.this,
                    "Are you sure you want to quit?",
                    "Exit Dialog", JOptionPane.YES_NO_OPTION,
                    JOptionPane.WARNING_MESSAGE, null, null,
                    null );
            if( option == JOptionPane.YES_OPTION ) {
                System.exit( 0 );
            }
        }
    }
}

-Nate

Yes Nathan,
You're absolutely right, of course. I suppose I should have tested some code before mouthing off.
Well I've learned something new today

Terry

Hmm, but it didn't work for me !!!
I'm developing it in Visual Age, so it takes some chopping about to post code. Maybe I'll have to do that, cos I definitely set the default Close operation to do nothing, and it just goes off and closes all by itself, no matter what I tell it to do...

Make sure that Visual Age isn't inserting any propriatary API calls (i.e. com.ibm.*) if you are generating code, and also see if any other listeners are being added to your frame... even if you set your frame to do nothing on close, if there is a listener, or if the frame uses processWindowEvent(), it will still exit.

-Nate