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Why glass pane requires setLightWeightPopupEnabled(false)?

800351Dec 10 2007 — edited Dec 13 2007
In the code below, the glass pane is a JPanel which everybody knows is a Swing lightweight component. Then why JComboBox requires setLightWeightPopupEnabled(false) for its proper functioning? What on earth does the method, in the first place? Why glass pane? What oddity in the hell does the glass pane have that other Swing component doesn't, never? 
import javax.swing.*;
import java.awt.*;

public class GlassPaneOddity{

  public static void main(String[] args){

    JFrame frame = new JFrame();
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    JPanel gp = new JPanel(new BorderLayout());
    frame.setGlassPane(gp);

    JComboBox cb 
      = new JComboBox(new String[]{"alpha", "beta", "gamma", "delta"});
    cb.setLightWeightPopupEnabled(false); // why this line is so critical?
    gp.add(cb, BorderLayout.NORTH);

    frame.setSize(300, 300);
    frame.setVisible(true);
    gp.setVisible(true);
  }
}

Comments

794342
add the indicated line and it should work
(but you may get other problems, look you don't want, color etc)
public static void main(String[] args){
  SwingUtilities.invokeLater(new Runnable(){
    public void run(){
      JDialog.setDefaultLookAndFeelDecorated(true);//<-----------
      new FileChooserSizeTest();
}});
}
843805
Michael_Dunn
yes it works! if I add JDialog.setDefaultLookAndFeelDecorated(true);

but that's the only way you know?
because yes it give me looks and feel problems my project :(
794342
the only other way I've seen is to add a componenLlistener,
and in componentResized() check the dimension - if under the min, reset to min
but I've not seen anyone happy with this solution - the component can be
dragged to small size, then 'snaps back' to the minimum
843805
the only other way I've seen is to add a
componenLlistener,
and in componentResized() check the dimension - if
under the min, reset to min
but I've not seen anyone happy with this solution -
the component can be
dragged to small size, then 'snaps back' to the
minimum
I think one of the changes introduced in Java 6 is that setMinimumSize() on a Window will actually enforce the set size, meaning that the window size will "freeze" if the user tries to make it smaller. I haven't tried this myself though, so I won't vouch for it.
843805
...and I see now that the OP mentions he is already using Java 6, so never mind.
843805
Try creating the file chooser like this
                JFileChooser fc = new JFileChooser(){
                    protected JDialog createDialog(Component parent) throws HeadlessException {
                        JDialog dialog = super.createDialog(parent);
                        dialog.setMinimumSize(new Dimension(200,200));
                        return dialog;
                    }
                };
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Post Details

Locked on Jan 10 2008
Added on Dec 10 2007
#swing
8 comments
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