🚀 go-pugleaf

apologies for posting this thrice...I thought the deletes worked when I
posted this at home.  But now I'm viewing this from work and I still see the
original two posts...Pl ignore.


"GEORGE" <geo@nowhere.net> wrote in message
news:4264611d$1@newsgroups.borland.com...
> I am posting a runnable version of my "app".  There are 3 buttons (for
> Motif, Metal and Window) in the JDialog subclass.  If I change the L&F
> "directly" in the action handler for the buttons there is no problem.
> However if I just set a Preferences object in the action handler with the
> chosen look and feel and make the JDialog subclass a
> PreferenceChangeListener (as shown below) then I get an NPE: and not
always
> on the first button click.
>
> I would like to get it to work the second way because in my real app, I'd
> like to be able to inform all the other containers of the L&F change by
> making all of them implement PreferenceChangeListener.  If there is a
better
> way to accomplish this, please let me know.
>
> TIA
> George
> --------------------------------------------------------------------------
--------------------------------------
> package configuration;
>
> import javax.swing.*;
> import java.awt.GridBagConstraints;
> import java.awt.GridBagLayout;
> import java.awt.Insets;
> import java.awt.event.ActionEvent;
> import java.util.prefs.*;
> import com.georgex.util.LookAndFeelHandler;
>
> /**
>  * <p>Title: </p>
>  *
>  * <p>Description: </p>
>  *
>  * <p>Copyright: Copyright (c) 2005</p>
>  *
>  * <p>Company: </p>
>  *
>  * @author
>  * @version 1.0
>  */
> public class OptionsDialog1 extends JDialog
>   implements PreferenceChangeListener
> {
>  public OptionsDialog1() throws Exception {
>     init();
>  }
>
>  public static void main(String[] args) {
>   try {
>    OptionsDialog1 optionsdialog1 = new OptionsDialog1();
>    optionsdialog1.setVisible(true);
>   } catch (Exception ex) {
>       ex.printStackTrace();
>     }
>  }
>
>   private  void init() throws Exception {
>     userPreferences = Preferences.userRoot();
>     this.setTitle("Configuration Options");
>     this.setModal(true);
>     this.setSize(500,500);
>
>     scrollPane1.setViewportView(tree);
>     scrollPane2.setViewportView(panel);
>     splitPane.setOrientation(JSplitPane.HORIZONTAL_SPLIT);
>     splitPane.setDividerLocation(150);
>     splitPane.setLeftComponent(scrollPane1);
>     splitPane.setRightComponent(scrollPane2);
>     splitPane.setOneTouchExpandable(true);
>     userPreferences.addPreferenceChangeListener(this);
>
>     this.getContentPane().setLayout(new GridBagLayout());
>     this.getContentPane().add(splitPane, new
> GridBagConstraints(0,0,1,1,1,1,GridBagConstraints.CENTER,
> GridBagConstraints.BOTH, new Insets(20,10,0,10),0,0));
>     this.getContentPane().add(metalButton, new
> GridBagConstraints(0,1,1,1,1,0,GridBagConstraints.EAST,
> GridBagConstraints.NONE, new Insets(20,0,20,50),0,0));
>     this.getContentPane().add(motifButton, new
> GridBagConstraints(1,1,1,1,0,0,GridBagConstraints.EAST,
> GridBagConstraints.NONE, new Insets(20,10,20,0),0,0));
>     this.getContentPane().add(windowsButton, new
> GridBagConstraints(2,1,1,1,0,0,GridBagConstraints.EAST,
> GridBagConstraints.NONE, new Insets(20,10,20,0),0,0));
>
>     metalButton.addActionListener(new AbstractAction() {
>       public void actionPerformed(ActionEvent e) {
>         try {
> //
UIManager.setLookAndFeel("javax.swing.plaf.metal.MetalLookAndFeel");
> //     setLAF();
>           userPreferences.putInt("LOOK_AND_FEEL", METAL);
>     } catch (Exception ex) {}
>       }
>     });
>     motifButton.addActionListener(new AbstractAction() {
>       public void actionPerformed(ActionEvent e) {
>         try {
> //     UIManager.setLookAndFeel(
> //      "com.sun.java.swing.plaf.motif.MotifLookAndFeel");
>           userPreferences.putInt("LOOK_AND_FEEL", MOTIF);
>      setLAF();
>     }catch (Exception ex) {}
>       }
>     });
>
>     windowsButton.addActionListener(new AbstractAction() {
>       public void actionPerformed(ActionEvent e) {
>         try {
> //
>
UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel
");
> //        setLAF();
>           userPreferences.putInt("LOOK_AND_FEEL", WINDOWS);
>       } catch (Exception ex) {}
>       }
>     });
>
>   }
>
>     public void preferenceChange(PreferenceChangeEvent e) {
>       System.out.println(e.getKey());
>       try {
>       int laf = userPreferences.getInt("LOOK_AND_FEEL", METAL);
>       switch (laf) {
>        case MOTIF:
>
UIManager.setLookAndFeel("com.sun.java.swing.plaf.motif.MotifLookAndFeel");
>          SwingUtilities.updateComponentTreeUI(this);
>          return;
>        case WINDOWS:
>
UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel
");
>          SwingUtilities.updateComponentTreeUI(this);
>          return;
>        default:
>
UIManager.setLookAndFeel("javax.swing.plaf.metal.MetalLookAndFeel");
>          SwingUtilities.updateComponentTreeUI(this);
>         return;
>       }
>       } catch (Exception ex) {}
>     }
>
>   private void setLAF() {
>     SwingUtilities.updateComponentTreeUI(this);
>
>   }
>
>   JSplitPane splitPane = new JSplitPane();
>   JScrollPane scrollPane1 = new JScrollPane();
>   JScrollPane scrollPane2 = new JScrollPane();
>   JTree tree = new JTree();
>   JPanel panel = new JPanel();
>   JButton motifButton = new JButton("Motif");
>   JButton metalButton = new JButton("Metal");
>   JButton windowsButton = new JButton("Windows");
>   Preferences userPreferences;
>   public static final int METAL = 0;
>   public static final int MOTIF = 1;
>   public static final int WINDOWS = 2;
> }
>
>
>
>
>
>
> --------------------------------------------------------------------------
---------------------------------------
> "Lori M Olson [TeamB]" <javadragon@techie.com> wrote in message
> news:426131bc$1@newsgroups.borland.com...
> > GEORGE wrote:
> >
> >> I am using the code below to change the look and feel of my app using 3
> >> radio buttons for Metal, Motif and Windows.
> >>
> >> The L & F changes alright.  But I get a null pointer exception along
the
> >> way.  The stack trace is also shown below but I am unable to make much
of
> >> it.  Any help would be appreciated.
> >>
> >> TIA
> >> George
> >>
> >
> > What leads you to believe that piece of code is responsible?  It's not
> > part of the stack trace?  Is it that the problem goes away if you
comment
> > out that code or something like that?
> >
> > I suspect that your code is simply exposing an different, underlying
> > problem.  Reading stack traces of Swing bugs is usually a thankless
task.
> > I really hate finding NPE's in the JDK.  If you run in the debugger, you
> > can click on those line numbers and go directly to the line on which the
> > NPE happened.  Looks like something needed a preferred size to be set,
and
> > it was not.  But that's just a wild guess.
> >
> > -- 
> >
> > Regards,
> >
> > Lori Olson [TeamB]
> >
> > ------------
> >
> > Save yourself, and everyone else, some time and search the
> > newsgroups and the FAQ-O-Matic before posting your next
> > question.
> >
> > Google Advanced Newsgroup Search
> >     http://www.google.ca/advanced_group_search
> > Other Newsgroup Searches:
> >     http://www.borland.com/newsgroups/ngsearch.html
> > Joi Ellis's FAQ-O-Matic:
> >     http://www.visi.com/~gyles19/fom-serve/cache/1.html
>
>
>