🚀 go-pugleaf

I wrote:
>(1) When I make the dialog taller (as a user, dragging it at runtime), the
>list [I assume] expands, adding white space after the end of the list. This
>is fine. But when I then make the dialog box slightly shorter, a scroll bar
>is added and I can scroll to a completely blank area. What should happen,
>IMHO, is for the JList to remove the blank space and just become
'naturally'
>shorter, still with no scroll bar. What am I missing?

I've got a little further with this, and I attach some simple source below
that demonstrates the problem.  It doesn't seem to matter what the window
type is, nor what layout manager is used. A standard JB app shell creates a
MyFrame. If the line marked /* THE PROBLEM */ is commented out, it runs OK;
with it in, it shows the problem above.

Can anybody explain this to me, please?

Thanks, Dave


package ListTests;

import java.awt.*;
import java.awt.event.*;
import com.sun.java.swing.*;

public class MyFrame extends JFrame
{
    //Construct the frame
    JList jList = new JList(new String[] {"one", "two", "three"});
    JScrollPane jScrollPane = new JScrollPane();

    public MyFrame()
    {
        enableEvents(AWTEvent.WINDOW_EVENT_MASK);
        try
        {
            jbInit();
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }
    }

    //Component initialization
    private void jbInit() throws Exception
    {
        jList.setPreferredSize(new Dimension(50, 50)); /* THE PROBLEM */
        jScrollPane.getViewport().add(jList, null);
        this.getContentPane().add(jScrollPane, null);
    }

    //Overriden so we can exit on System Close
    protected void processWindowEvent(WindowEvent e)
    {
        super.processWindowEvent(e);
        if (e.getID() == WindowEvent.WINDOW_CLOSING)
            System.exit(0);
    }
}

/*****************/

PS  I went to the bookshop yesterday and looked at the O'Reilly Java Swing
book.  Naturally, I looked at their first JList example and spotted a bug
(they didn't bind the model to the view).  Didn't inspire much confidence in
the book :-(  Are there any better ones?