How to insure selected tabs are visible in JTabbedPane

Question

Hello all,
How can you insure that the selected tab in a JTabbedPane is visible.
Here is the code:
import javax.swing.*;
import java.awt.*;
public class TabbedPaneTest extends JTabbedPane implements Runnable
public TabbedPaneTest()
super(JTabbedPane.TOP, JTabbedPane.SCROLL_TAB_LAYOUT);
} // end TabbedPaneTest constructor
public void run ()
for (int i = 1; i <= 10; i ++)
try
this.addTab(Integer.toString(i), createDefaultPanel (i));
this.getModel().setSelectedIndex(i - 1);
Thread.sleep(3000);
} // end try block
catch (Exception e)
e.printStackTrace();
} // end catch block
} // end for loop
} // end run method
private JPanel createDefaultPanel (int index)
JPanel defaultPanel = new JPanel ();
defaultPanel.setBorder(BorderFactory.createTitledBorder(BorderFactory.createLoweredBevelBorder(), Integer.toString(index)));
return defaultPanel;
} // end createDefaultPanel method
public static void main (String args [])
JFrame frame = new JFrame ();
TabbedPaneTest tpt = new TabbedPaneTest ();
frame.getContentPane().add(tpt);
frame.setSize(200, 200);
Thread newThread = new Thread (tpt);
newThread.start();
frame.setVisible(true);
} // end main method
} // end TabbedPaneTest class
I've crated a JTabbedPane with the tabLayoutPolicy set to JTabbedPane.SCROLL_TAB_LAYOUT.
If I add enough tabs the scroll buttons appear but the newly adde tab is hidden behind them,
even though I have set the selection index to the added tab. The content of the panel associated
with the tab is visible but the tab itself is hidden.
So the selected tab is hidden behind the scroll buttons.
Any one know how to insure that if a tab is selected it is visible to the user.
Thanks

Answer 1

This is an interesting question so I tried it out. After some poking around to see how Swing does this for mouse clicking (try setting things up so that a tab is only partially visible and then click on the visable part - notice how the whole tab is scrolled into view) I found this:    /**
     * This inner class is marked "public" due to a compiler bug.
     * This class should be treated as a "protected" inner class.
     * Instantiate it only within subclasses of BasicTabbedPaneUI.
    public class TabSelectionHandler implements ChangeListener {
        public void stateChanged(ChangeEvent e) {
            JTabbedPane tabPane = (JTabbedPane)e.getSource();
            tabPane.revalidate();
            tabPane.repaint();
            if (tabPane.getTabLayoutPolicy() == JTabbedPane.SCROLL_TAB_LAYOUT) {
                int index = tabPane.getSelectedIndex();
                if (index < rects.length && index != -1) {
                    tabScroller.tabPanel.scrollRectToVisible(rects[index]);
    }Which is called when the selected tab changes. The member theScroller is a private inner class that handles the scrolling tabs. The call to scrollRectToVisible is executed for each of your new tabs. Sometimes when I stopped in the debugger and then continued things worked and your new tab scrolled into view.
So I tried putting your code into a Runnable class and invoked it later:          final int newIndex = i;
          SwingUtilities.invokeLater (new Runnable ()  {
               public void run ()  {
                    addTab(Integer.toString(newIndex), createDefaultPanel (newIndex));
                    getModel().setSelectedIndex(newIndex - 1);
          });But that did not work. That is as far as I got so far and I have to stop now. Perhaps this can inspire someone else to a solution.
IL
PS. I first tried Rammensee's solution and it did not work.
Rammensee, you said you hoped you had it right - perhaps you are close.