To make TAB out of JTextArea

Question

Hi,
I found someone post the following code inthe forum. It supposes
to trap the tab key and move the focus to the next component, instead
of having the tab in the JTextArea. I got it complied okay, but I
received exception when executing:
java.lang.ClassCastException: javax.swing.KeyStroke
at java.util.TreeMap.compare(TreeMap.java:1081)
at java.util.TreeMap.put(TreeMap.java:459)
at java.util.TreeSet.add(TreeSet.java:205)
The exeception is from the 3rd line of the codes.
Please help!!!
Pin
Codes...
Set forwardTraversalKeys = new TreeSet();
forwardTraversalKeys.add(KeyStroke.getKeyStroke('\t'));
forwardTraversalKeys.add(KeyStroke.getKeyStroke(KeyEvent.VK_TAB,
InputEvent.CTRL_MASK));
textArea.setFocusTraversalKeys
(KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS,
forwardTraversalKeys);
Set backwardTraversalKeys = new TreeSet();
backwardTraversalKeys.add(KeyStroke.getKeyStroke(KeyEvent.VK_TAB,
InputEvent.SHIFT_MASK));
backwardTraversalKeys.add(KeyStroke.getKeyStroke(KeyEvent.VK_TAB,
InputEvent.SHIFT_MASK |InputEvent.CTRL_MASK));
textArea.setFocusTraversalKeys( KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS, backwardTraversalKeys);

Answer 1

Sorry about my last post. I just cut and pasted some code from an example that uses a background image in the text area and should have deleted the paintComponent() method. Here is the complete code in case you want to try again. This works in JDK1.3. I know focus management has changed in JDK1.4, but you don't mention which version you are using.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.text.*;
public class BackgroundFloating extends JFrame
     JTextArea textArea;
     JScrollPane scrollPane;
     ImageIcon image;
     public BackgroundFloating()
          image = new ImageIcon("???.jpg");
          textArea = new JTextArea( "one two", 10, 30 )
               public void paintComponent(Graphics g)
                    Point p = scrollPane.getViewport().getViewPosition();
                    g.drawImage(image.getImage(), p.x, p.y, null);
                    super.paintComponent(g);
               //  the tab character is not inserted into the text area
               public boolean isManagingFocus()
                    return false;
          textArea.setOpaque(false);
          textArea.setFont( new Font("monospaced", Font.PLAIN, 12) );
          textArea.setLineWrap( true );
          textArea.setWrapStyleWord( true );
          scrollPane = new JScrollPane( textArea );
          getContentPane().add( scrollPane );
          getContentPane().add( new JTextField(20), BorderLayout.SOUTH );
     public static void main(String[] args)
          BackgroundFloating frame = new BackgroundFloating();
          frame.setDefaultCloseOperation( EXIT_ON_CLOSE );
          frame.pack();
          frame.setVisible(true);
}