Setting JScrollPane position

Question

I have a JScrollPane which has a JList (of sorted strings) as its view. When the list has the focus and the user presses a key, the first item that starts with the pressed key is selected. But the the JScrollPane does not scroll to this position and I'd like to add this feature.
What I have tried is (in valueChanged())
scrollPane.getVerticalScrollBar().setValue(list.getSelectedIndex());but this does not work. How can I set the scroll position to a certain value?

Answer 1

What I have tried is (in valueChanged())Show the sample program you used to test your code. It works fine for me:
import java.awt.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.text.*;
public class ListScrollToSelected extends JFrame implements ListSelectionListener
    public ListScrollToSelected()
        String[] data = { "a", "b", "c", "d", "e", "f", "g", "h", "i", "j" };
        JList list = new JList( data )
            public int getNextMatch(String prefix, int startIndex, Position.Bias bias)
                int row = super.getNextMatch(prefix, startIndex, bias);
//                ensureIndexIsVisible( row );
                return row;
        list.setVisibleRowCount(5);
        list.setSelectedIndex(0);
        list.addListSelectionListener( this );
        JScrollPane scrollPane = new JScrollPane( list );
        getContentPane().add( scrollPane );
    public void valueChanged(ListSelectionEvent e)
        if (e.getValueIsAdjusting()) return;
        JList list = (JList)e.getSource();
        list.ensureIndexIsVisible( list.getSelectedIndex() );
    public static void main(String[] args)
        ListScrollToSelected frame = new ListScrollToSelected();
        frame.setDefaultCloseOperation( EXIT_ON_CLOSE );
        frame.pack();
        frame.setLocationRelativeTo( null );
        frame.setVisible( true );
}I also included a second way to do this by overriding the getNextMatch(...) method.