Why the vertical scrollbar bar is automatically scrolled to the bottom pos.

Question

I created a JScrollpane to contain a JTabbedPane. The JTabbedPane has two JPanel and each of them has a number of GUI components such as JCheckbox and JTextField. They have different size because their GUI components are different. The 2nd panel is about twice the size of the first panel.
When the JScrollpane is shown, its vertical scroll bar is automatically scrolled to the bottom position. However, it is the first panel that is initially visible to the user. So, the user will see no GUI components of the first panel because the auto scrolling of the vertical scroll bar.
Can anyone tell me how to disable the auto scrolling?
I just want to let the scrollbar knob stay at the top so that the GUI components of the first panel (the smaller one) can be seen initially!

Answer 1

Works fine for me:
import javax.swing.*;
import java.awt.*;
public class TabbedPaneScroll extends JFrame
     private JTabbedPane tabbedPane;
     public TabbedPaneScroll()
          tabbedPane = new JTabbedPane();
          tabbedPane.setPreferredSize( new Dimension(300, 200) );
          getContentPane().add(tabbedPane);
          addNewTab( 10 );
          addNewTab( 5 );
          addNewTab( 20 );
     private void addNewTab(int fields)
          JPanel panel = new JPanel();
          panel.setLayout( new GridLayout(0, 1) );
          for (int i = 0; i < fields; i++)
               panel.add( new JTextField("" + i) );
          JScrollPane scrollPane = new JScrollPane( panel );
          tabbedPane.add(scrollPane, "" + fields);
     public static void main(String args[])
          TabbedPaneScroll frame = new TabbedPaneScroll();
          frame.setDefaultCloseOperation( EXIT_ON_CLOSE );
          frame.pack();
          frame.setLocationRelativeTo( null );
          frame.setVisible(true);
}If you need further help then you need to create a [url http://www.physci.org/codes/sscce.jsp]Short, Self Contained, Compilable and Executable, Example Program that demonstrates the incorrect behaviour, because I can't guess exactly what you are doing based on the information provided.
And don't forget to use the [url http://forum.java.sun.com/help.jspa?sec=formatting]Code Formatting Tags so the code retains its original formatting.