Pressing ALT obscures components when using Windows L&F

U

ub

I have a JFrame that displays a big JLabel in the background and a
JCheckBox in the front.

When using the Windows L&F and I press the Alt-key the JLabel is
repainted but not the JCheckBox in front of it. As a consequence the
checkbox disappears. Forcing a repaint (e.g. by resizing the frame)
will make the checkbox re-appear.

When not using the Window L&F everything is fine.

Any suggestion how to work around this problem?

ub


Here the sourcecode:
-----
import java.awt.Color;

import javax.swing.JCheckBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.UnsupportedLookAndFeelException;

public class AltKeyRepaint {
public static void main(String args[]) throws ClassNotFoundException,
InstantiationException, IllegalAccessException,
UnsupportedLookAndFeelException {
// Use the System (i.e. "Windows") L&F
javax.swing.UIManager.setLookAndFeel(javax.swing.UIManager
.getSystemLookAndFeelClassName());

// The frame to display the sample
JFrame frame = new JFrame("Frame");
frame.setSize(250, 200);
frame.getContentPane().setLayout(null);

// A big colored label in the background
JLabel label = new JLabel("A sample label in the background");
label.setBackground(Color.ORANGE);
label.setOpaque(true);
label.setBounds(5, 5, 200, 150);

// A check box on top of the background label
JCheckBox chkBox = new JCheckBox("a check box on top");
chkBox.setBounds(30, 30, 150, 20);

// Add the label and check box to the frame
frame.getContentPane().add(chkBox);
frame.getContentPane().add(label);

// display it
frame.show();

// Now pressing the ALT key will repaint the label, but not the
// check box, i.e. the check box disappears.
// Forcing a repaint (e.g. by resizing the frame) will make the
check
// box re-appear.

// Without the Windows L&F (first statement of function) everything
// will be fine.
}
}
 
A

Andrew Thompson

so dont use ..

- Punctuation in words like don't?
- Restraint when posting 4 of the same reply?
- Inline trimming posting in replies?

None of those things will solve the OP's stated problem,
which relates mostly to poor use of layouts.

(When I get home later, I will test some altered source
that should solve the *stated* problem.)
 
J

Joe Blow

duh

Smith said:
so dont use windows l&f

ub said:
I have a JFrame that displays a big JLabel in the background and a
JCheckBox in the front.

When using the Windows L&F and I press the Alt-key the JLabel is
repainted but not the JCheckBox in front of it. As a consequence the
checkbox disappears. Forcing a repaint (e.g. by resizing the frame)
will make the checkbox re-appear.

When not using the Window L&F everything is fine.

Any suggestion how to work around this problem?

ub


Here the sourcecode:
-----
import java.awt.Color;

import javax.swing.JCheckBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.UnsupportedLookAndFeelException;

public class AltKeyRepaint {
public static void main(String args[]) throws ClassNotFoundException,
InstantiationException, IllegalAccessException,
UnsupportedLookAndFeelException {
// Use the System (i.e. "Windows") L&F
javax.swing.UIManager.setLookAndFeel(javax.swing.UIManager
.getSystemLookAndFeelClassName());

// The frame to display the sample
JFrame frame = new JFrame("Frame");
frame.setSize(250, 200);
frame.getContentPane().setLayout(null);

// A big colored label in the background
JLabel label = new JLabel("A sample label in the background");
label.setBackground(Color.ORANGE);
label.setOpaque(true);
label.setBounds(5, 5, 200, 150);

// A check box on top of the background label
JCheckBox chkBox = new JCheckBox("a check box on top");
chkBox.setBounds(30, 30, 150, 20);

// Add the label and check box to the frame
frame.getContentPane().add(chkBox);
frame.getContentPane().add(label);

// display it
frame.show();

// Now pressing the ALT key will repaint the label, but not the
// check box, i.e. the check box disappears.
// Forcing a repaint (e.g. by resizing the frame) will make the
check
// box re-appear.

// Without the Windows L&F (first statement of function) everything
// will be fine.
}
}
 
A

Andrew Thompson

ub said:
I have a JFrame that displays a big JLabel in the background and a
JCheckBox in the front.

The JCB is actually 'above' the JL, here.
When using the Windows L&F and I press the Alt-key the JLabel is
repainted but not the JCheckBox in front of it. As a consequence the
checkbox disappears. Forcing a repaint (e.g. by resizing the frame)
will make the checkbox re-appear.

When not using the Window L&F everything is fine.

I did not see the stated problem, either way, but
noticed the very fragile code being used.
Any suggestion how to work around this problem?

Use layouts. This might not be exactly what you
want, it might require a nested layout to get the
full effect, but it is perhaps a starting point..

<sscce>
import java.awt.*;
import javax.swing.*;
import javax.swing.border.*;
import javax.swing.UnsupportedLookAndFeelException;

public class AltKeyRepaint {
public static void main(String args[]) throws ClassNotFoundException,
InstantiationException, IllegalAccessException,
UnsupportedLookAndFeelException {
// Use the System (i.e. "Windows") L&F
// ie only if the user is Window'd
// otherwise it will be the Mac. or *nix style PLAF's
javax.swing.UIManager.setLookAndFeel(javax.swing.UIManager
.getSystemLookAndFeelClassName());

// The frame to display the sample
JFrame frame = new JFrame("Frame");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

// this is probably not only the source of the
// current problems, but a dozen others that
// have either not been seen, or not manifested yet.
// Do not use 'null' layouts unless you..
// a) know what your doing, (and potentially also..)
// b) are designing a custom layout,
// frame.getContentPane().setLayout(null);
JPanel p = new JPanel(new BorderLayout());
p.setBackground(Color.ORANGE);

// A big colored label in the background
JLabel label = new JLabel("A sample label in the CENTER",
JLabel.CENTER);
label.setOpaque(false);
// play with the padding numbers,
// to get the right effect..
label.setBorder( new EmptyBorder(30,15,50,15) );

// A check box on top of the background label
JCheckBox chkBox = new JCheckBox("a check box in NORTH");
chkBox.setOpaque(false);
chkBox.setBorder( new EmptyBorder(20,5,20,5) );

// Add the label and check box to the frame
p.add(chkBox, BorderLayout.NORTH);
p.add(label, BorderLayout.CENTER);

frame.getContentPane().add(p);

// display it
// deprecated in Java 1.2/1.5
// frame.show();

// this cause everything to become the
// preferred size, which might be different
// on different platforms, PLAF's, font sizes,
// Java versions, or screen resolutions.
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}
</sscce>

HTH

--
Andrew Thompson
http://www.athompson.info/andrew/

Message posted via JavaKB.com
http://www.javakb.com/Uwe/Forums.aspx/java-general/200704/1
 
U

ub

The code I presented is the smallest code sample I could come up to
show the problem I ran into. Using the "null" layout was the simplest
way to demonstrate the issue. Actually a custom-made LayoutManager is
used in the real application but shows exactly the same behaviour as
the "null" layout.

The "real" application is part of an "AWT to Swing" porting project.
In that application the components are created dynamically, based on
some "form definitions" that define the location and size of the
individual components. Because of the amount and size of these
definitions (>8000, typically more than 10 components in each form)
rewriting the layout is not really an option.

I did some more tests and it looks like the issue also depends on the
graphic card. When using a DVI output the button disappears, but on a
VGA output everything is fine. So it may be a driver issue. Does that
makes sense?


ub




ub said:
I have a JFrame that displays a big JLabel in the background and a
JCheckBox in the front.

The JCB is actually 'above' the JL, here.
When using the Windows L&F and I press the Alt-key the JLabel is
repainted but not the JCheckBox in front of it. As a consequence the
checkbox disappears. Forcing a repaint (e.g. by resizing the frame)
will make the checkbox re-appear.
When not using the Window L&F everything is fine.

I did not see the stated problem, either way, but
noticed the very fragile code being used.
Any suggestion how to work around this problem?

Use layouts. This might not be exactly what you
want, it might require a nested layout to get the
full effect, but it is perhaps a starting point..

<sscce>
import java.awt.*;
import javax.swing.*;
import javax.swing.border.*;
import javax.swing.UnsupportedLookAndFeelException;

public class AltKeyRepaint {
public static void main(String args[]) throws ClassNotFoundException,
InstantiationException, IllegalAccessException,
UnsupportedLookAndFeelException {
// Use the System (i.e. "Windows") L&F
// ie only if the user is Window'd
// otherwise it will be the Mac. or *nix style PLAF's
javax.swing.UIManager.setLookAndFeel(javax.swing.UIManager
.getSystemLookAndFeelClassName());

// The frame to display the sample
JFrame frame = new JFrame("Frame");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

// this is probably not only the source of the
// current problems, but a dozen others that
// have either not been seen, or not manifested yet.
// Do not use 'null' layouts unless you..
// a) know what your doing, (and potentially also..)
// b) are designing a custom layout,
// frame.getContentPane().setLayout(null);
JPanel p = new JPanel(new BorderLayout());
p.setBackground(Color.ORANGE);

// A big colored label in the background
JLabel label = new JLabel("A sample label in the CENTER",
JLabel.CENTER);
label.setOpaque(false);
// play with the padding numbers,
// to get the right effect..
label.setBorder( new EmptyBorder(30,15,50,15) );

// A check box on top of the background label
JCheckBox chkBox = new JCheckBox("a check box in NORTH");
chkBox.setOpaque(false);
chkBox.setBorder( new EmptyBorder(20,5,20,5) );

// Add the label and check box to the frame
p.add(chkBox, BorderLayout.NORTH);
p.add(label, BorderLayout.CENTER);

frame.getContentPane().add(p);

// display it
// deprecated in Java 1.2/1.5
// frame.show();

// this cause everything to become the
// preferred size, which might be different
// on different platforms, PLAF's, font sizes,
// Java versions, or screen resolutions.
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}}

</sscce>

HTH
 
A

Andrew Thompson

ub wrote:

Please refrain from top-posting in future. I
find it most confusing.
The code I presented is the smallest code sample I could come up to
show the problem I ran into.

The problem did not display here.
..Using the "null" layout was the simplest
way to ...

..introduce further problems that obscure the issue?
..demonstrate the issue. Actually a custom-made LayoutManager is
used in the real application but shows exactly the same behaviour as
the "null" layout.

The first thing usually done in a custom layout manager
(as mentioned in my post) is to setLayout(null). If the
author of that custom layout showed as little
understanding of the complexities of creating a
layout as was demonstrated in the posted example,
it is just as broken as the posted code.
...rewriting the layout is not really an option.
(snip..)

Sounds as though you are up sh*t creek, without
a paddle, if you are limited as to how to approach
solutions. Good luck with it.

--
Andrew Thompson
http://www.athompson.info/andrew/

Message posted via JavaKB.com
http://www.javakb.com/Uwe/Forums.aspx/java-general/200704/1
 
A

Andrew Thompson

ub wrote:

Please refrain from top-posting in future. I
find it most confusing.
The code I presented is the smallest code sample I could come up to
show the problem I ran into.

The problem did not display here.
..Using the "null" layout was the simplest
way to ...

..introduce further problems that obscure the issue?
..demonstrate the issue. Actually a custom-made LayoutManager is
used in the real application but shows exactly the same behaviour as
the "null" layout.

The first thing usually done in a custom layout manager
(as mentioned in my post) is to setLayout(null). If the
author of that custom layout showed as little
understanding of the complexities of creating a
layout as was demonstrated in the posted example,
it is just as broken as the posted code.
...rewriting the layout is not really an option.
(snip..)

Sounds as though you are up sh*t creek, without
a paddle, if you are limited as to how to approach
solutions. Good luck with it.

--
Andrew Thompson
http://www.athompson.info/andrew/

Message posted via JavaKB.com
http://www.javakb.com/Uwe/Forums.aspx/java-general/200704/1
 
R

Real Gagnon

I did some more tests and it looks like the issue also depends on the
graphic card. When using a DVI output the button disappears, but on a
VGA output everything is fine. So it may be a driver issue. Does that
makes sense?

Try to disable the direct draw feature with :

java -Dsun.java2d.noddraw=true <class>

Bye.
 
U

ub

Try to disable the direct draw feature with :
java -Dsun.java2d.noddraw=true <class>

Thanks for the tip.

I tried it but nothing changed.


But I "upgraded" the JRE from 1.4.2_6 to 1.5 and the problem is gone.
So it looks like it was related to a bug in the JRE that was fixed
after 1.4.2.

Thanks to everybody for your support,

ub
 

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