Name: jk109818 Date: 01/08/2002


FULL PRODUCT VERSION :
C:\java\dev>java -version
java version "1.3.1_01"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.3.1_01)
Java HotSpot(TM) Client VM (build 1.3.1_01, mixed mode)

FULL OPERATING SYSTEM VERSION : Windows NT Version 4.0




A DESCRIPTION OF THE PROBLEM :
When a shown JTabbedPane's tabs are removed, readded, and
revalidated, the initially shown tab/panel is not layed out
and appears as blank.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Build a JTabbedPane with multiple tabs. Show it. Make sure
the 0th tab is selected. Remove all of the tabs. Re-add all
of the tabs. The shown tab will appear as blank and unlayed
out / empty. You have to click off of and then back onto
the initial tab to get the 0th tab to show layed out at all.

Side Note: If you click off of the 0th tab before removing
the panels, when you add the tabs back the 0th tab will be
selected and shown correctly.

Run the attached test code and click the Rebuild button.
The initially shown content, "Content TestPanel #0"
disappears, until you select a different tab, and then
reselect the "TestPanel #0" tab.

Side Note: If you select one of the other tabs before
clicking the Rebuild button the performance is correct.

EXPECTED VERSUS ACTUAL BEHAVIOR :
When ever tabs are added to a JTabbedPane, I expect some
combination of (re)validate(Tree) and repaint to layout and
show the first tab added.

This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;

public class TabbedTest extends JFrame {

TabbedTest() {
getContentPane().add( mainPanel );
JButton rebuild = new JButton( "Rebuild" );
rebuild.addActionListener( new ActionListener() {
public void actionPerformed( ActionEvent ae ) {
rebuildTabbedPane();
}
} );
mainPanel.add( rebuild, BorderLayout.NORTH );
mainPanel.add( mainTabbedPane, BorderLayout.CENTER );
rebuildTabbedPane();
}

JPanel mainPanel = new JPanel( new BorderLayout() );

JTabbedPane mainTabbedPane = new JTabbedPane();

JPanel testPanels[] = null;
JPanel[] getTestPanels() {
if( testPanels == null ) {
testPanels = new JPanel[5];
for( int i = 0 ; i < 5; i++ ) {
JPanel testPanel = new JPanel();
testPanel.add( new JLabel( "Content TestPanel
#" + i ) );
testPanels[i] = testPanel;
}
}
return testPanels;
}

void rebuildTabbedPane() {
mainTabbedPane.removeAll();

for( int i = 0; i < 5; i++ )
mainTabbedPane.add( getTestPanels()[i], "TestPanel #" +
i );

mainTabbedPane.validate();
}

public static void main( String args[] ) {
TabbedTest tt = new TabbedTest();
tt.pack();
tt.show();
}
}

---------- END SOURCE ----------

CUSTOMER WORKAROUND :
I tried simulating the click off of and back onto the 0th
tab both prior to removing all of the tabs and after adding
all of the tabs without success. I tried bombarding my code
with calls to any of validate, revalidate, validateTree,
and repaint without success.
(Review ID: 138060)
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