JViewport Resize problem -- Urgent!

Question

I am trying to make a program that allows the user to dynamically resize a scrollable JPanel. I have added resize buttons that work well. The JScrollPane works well, but when the JViewport's View is set to the bottom right corner of the JPanel, and the user attempts to resize the JPanel, the JViewport repaints its view to the top left corner, hence undoing any resizing. Resizing should not change the View, even if the component is no longer visible in the view.
Here is a code example (please pardon the length and lack of comments):
import javax.swing.*;
import java.awt.*;
import javax.swing.event.*;
import java.awt.event.*;
public class JViewportBug extends JPanel implements Scrollable, ComponentListener
     public JViewportBug()
          this.setLayout( null );
     public Dimension getPreferredScrollableViewportSize()
          return getPreferredSize();
     public boolean getScrollableTracksViewportHeight()
          return false;
     public boolean getScrollableTracksViewportWidth()
          return false;
     public int getScrollableBlockIncrement( Rectangle visibleRect, int orientation, int direction )
          if( orientation == SwingConstants.VERTICAL )
               return (int)( visibleRect.getHeight() * 9 / 10 );
          return (int)( visibleRect.getWidth() * 9 / 10 );
     public int getScrollableUnitIncrement( Rectangle visibleRect, int orientation, int direction )
          return 5;
     public void componentHidden(ComponentEvent e)
     public void componentMoved(ComponentEvent e)
     public void componentResized(ComponentEvent e)
          Dimension size = ( (Component)e.getSource() ).getSize();
          this.setBounds( 0, 0, 20 + size.width, 20 + size.height );
          this.setPreferredSize( new Dimension( 20 + size.width, 20 + size.height ) );
     public void componentShown(ComponentEvent e)
     public static void main( String[] args )
          JViewportBug bug = new JViewportBug();
          JFrame frame = new JFrame( "JViewport Bug" );
          frame.setExtendedState( JFrame.MAXIMIZED_BOTH );
          JScrollPane jsp = new JScrollPane( bug );
          JPanel viewable = new JPanel();
          bug.add( viewable );
          viewable.addComponentListener( bug );
          viewable.setBounds( 10, 10, 200, 200 );
          JDesktopPane jdp = new JDesktopPane();
          jdp.setLayout( null );
          for( int i = 0; i < 8; i++ )
               ResizeButton rb = new ResizeButton( viewable, i, true );
               bug.add( rb );
               viewable.addComponentListener( rb );
          frame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
          viewable.setBackground( Color.white );
          frame.getContentPane().add( jdp, BorderLayout.CENTER );
          JInternalFrame jif = new JInternalFrame( "", true, true, true, true );
          jif.getContentPane().add( jsp );
          jdp.add( jif );
          jif.setSize( 500, 500 );
          bug.setPreferredSize( new Dimension( viewable.getWidth() + 20, viewable.getHeight() + 20 ) );
          jif.setVisible( true );
          frame.setVisible( true );
class ResizeButton extends JComponent implements MouseMotionListener, MouseListener, ComponentListener
     public static final int NW_RESIZE_BUTTON = 0;
     public static final int N_RESIZE_BUTTON = 1;
     public static final int NE_RESIZE_BUTTON = 2;
     public static final int E_RESIZE_BUTTON = 3;
     public static final int SE_RESIZE_BUTTON = 4;
     public static final int S_RESIZE_BUTTON = 5;
     public static final int SW_RESIZE_BUTTON = 6;
     public static final int W_RESIZE_BUTTON = 7;
     JComponent resize;
     int buttonType;
     boolean enabled;
     public ResizeButton( JComponent aComponent, int type, boolean isEnabled )
          resize = aComponent;
          buttonType = type;
          setBounds();
          enabled = isEnabled;
          this.addMouseMotionListener( this );
          this.addMouseListener( this );
     public int getType()
          return buttonType;
     public void mouseEntered( MouseEvent e )
          if( enabled )
               switch( ( (ResizeButton)e.getSource() ).getType() )
                    case 0:
                         getParent().setCursor( new Cursor( Cursor.NW_RESIZE_CURSOR ) );
                         break;
                    case 1:
                         getParent().setCursor( new Cursor( Cursor.N_RESIZE_CURSOR ) );
                         break;
                    case 2:
                         getParent().setCursor( new Cursor( Cursor.NE_RESIZE_CURSOR ) );
                         break;
                    case 3:
                         getParent().setCursor( new Cursor( Cursor.E_RESIZE_CURSOR ) );
                         break;
                    case 4:
                         getParent().setCursor( new Cursor( Cursor.SE_RESIZE_CURSOR ) );
                         break;
                    case 5:
                         getParent().setCursor( new Cursor( Cursor.S_RESIZE_CURSOR ) );
                         break;
                    case 6:
                         getParent().setCursor( new Cursor( Cursor.SW_RESIZE_CURSOR ) );
                         break;
                    case 7:
                         getParent().setCursor( new Cursor( Cursor.W_RESIZE_CURSOR ) );
     public void mouseExited( MouseEvent e )
          if( enabled )
               getParent().setCursor( new Cursor( Cursor.DEFAULT_CURSOR ) );
     public void mouseClicked( MouseEvent e )
     public void mousePressed( MouseEvent e )
     public void mouseReleased( MouseEvent e )
     public void mouseMoved( MouseEvent e )
     public void mouseDragged( MouseEvent e )
          if( enabled && e.getSource() instanceof ResizeButton )
               int clickedX = e.getX();
               int clickedY = e.getY();
               int width, height;
               switch( ( (ResizeButton)e.getSource() ).getType() )
                    case NW_RESIZE_BUTTON:
                         width = resize.getX() + resize.getWidth() - this.getX() - clickedX > 1 ? resize.getX() - this.getX() - clickedX + resize.getWidth() : 1;
                         height = ( resize.getY() + resize.getHeight() - this.getY() - clickedY > 1 ? resize.getY() - this.getY() - clickedY + resize.getHeight() : 1 );
                         resize.setBounds( resize.getX() + resize.getWidth() - this.getX() - clickedX > 1 ? this.getX() + clickedX : resize.getX() + resize.getWidth() - 1,
                                                       resize.getY() + resize.getHeight() - this.getY() - clickedY > 1 ? this.getY() + clickedY : resize.getY() + resize.getHeight() - 1,
                                                       width,
                                                       height );
                         break;
                    case N_RESIZE_BUTTON:
                         height = resize.getY() + resize.getHeight() - this.getY() - clickedY > 1 ? resize.getY() - this.getY() - clickedY + resize.getHeight() : 1;
                         resize.setBounds( resize.getX(),
                                                       resize.getY() + resize.getHeight() - this.getY() - clickedY > 1 ? this.getY() + clickedY : resize.getY() + resize.getHeight() - 1,
                                                       resize.getWidth(),
                                                       height );
                         break;
                    case NE_RESIZE_BUTTON:
                         width = this.getX() + clickedX - resize.getX() > 1 ? this.getX() + clickedX - resize.getX() : 1;
                         height = resize.getY() + resize.getHeight() - this.getY() - clickedY > 1 ? resize.getY() - this.getY() - clickedY + resize.getHeight() : 1;
                         resize.setBounds( resize.getX(),
                                                       resize.getY() + resize.getHeight() - this.getY() - clickedY > 1 ? this.getY() + clickedY : resize.getY() + resize.getHeight() - 1,
                                                       width,
                                                       height );
                         break;
                    case E_RESIZE_BUTTON:
                         width = this.getX() + clickedX - resize.getX() > 1 ? this.getX() + clickedX - resize.getX() : 1;
                         resize.setBounds( resize.getX(),
                                                       resize.getY(),
                                                       width,
                                                       resize.getHeight() );
                         break;
                    case SE_RESIZE_BUTTON:
                         width = this.getX() + clickedX - resize.getX() > 1 ? this.getX() + clickedX - resize.getX() : 1;
                         height = this.getY() + clickedY - resize.getY() > 1 ? this.getY() + clickedY - resize.getY() : 1;
                         resize.setBounds( resize.getX(),
                                                       resize.getY(),
                                                       width,
                                                       height );
                         break;
                    case S_RESIZE_BUTTON:
                         height = this.getY() + clickedY - resize.getY() > 1 ? this.getY() + clickedY - resize.getY() : 1;
                         resize.setBounds( resize.getX(),
                                                       resize.getY(),
                                                       resize.getWidth(),
                                                       height );
                         break;
                    case SW_RESIZE_BUTTON:
                         width = resize.getX() + resize.getWidth() - this.getX() - clickedX > 1 ? resize.getX() - this.getX() - clickedX + resize.getWidth() : 1;
                         height = this.getY() + clickedY - resize.getY() > 1 ? this.getY() + clickedY - resize.getY() : 1;
                         resize.setBounds( resize.getX() + resize.getWidth() - this.getX() - clickedX > 1 ? this.getX() + clickedX : resize.getX() + resize.getWidth() - 1,
                                                       resize.getY(),
                                                       width,
                                                       height );
                         break;
                    case W_RESIZE_BUTTON:
                         width = resize.getX() + resize.getWidth() - this.getX() - clickedX > 1 ? resize.getX() - this.getX() - clickedX + resize.getWidth() : 1;
                         resize.setBounds( resize.getX() + resize.getWidth() - this.getX() - clickedX > 1 ? this.getX() + clickedX : resize.getX() + resize.getWidth() - 1,
                                                       resize.getY(),
                                                       width,
                                                       resize.getHeight() );
     public void setBounds()
          switch( buttonType )
               case NW_RESIZE_BUTTON:
                    this.setBounds( resize.getX() - 5,
                                             resize.getY() - 5,
                                             5,
                                             5 );
                    break;
               case N_RESIZE_BUTTON:
                    this.setBounds( (int)( ( resize.getWidth() + 2 * resize.getX() ) / 2 ) - 2,
                                             resize.getY() - 5,
                                             5,
                                             5 );
                    break;
               case NE_RESIZE_BUTTON:
                    this.setBounds( resize.getWidth() + resize.getX(),
                                             resize.getY() - 5,
                                             5,
                                             5 );
                    break;
               case E_RESIZE_BUTTON:
                    this.setBounds( resize.getWidth() + resize.getX(),
                                             (int)( ( resize.getHeight() + 2 * resize.getY() ) / 2 ) - 2,
                                             5,
                                             5 );
                    break;
               case SE_RESIZE_BUTTON:
                    this.setBounds( resize.getWidth() + resize.getX(),
                                             resize.getHeight() + resize.getY(),
                                             5,
                                             5 );
                    break;
               case S_RESIZE_BUTTON:
                    this.setBounds( (int)( ( resize.getWidth() + 2 * resize.getX() ) / 2 ) - 2,
                                             resize.getHeight() + resize.getY(),
                                             5,
                                             5 );
                    break;
               case SW_RESIZE_BUTTON:
                    this.setBounds( resize.getX() - 5,
                                             resize.getHeight() + resize.getY(),
                                             5,
                                             5 );
                    break;
               case W_RESIZE_BUTTON:
                    this.setBounds( resize.getX() - 5,
                                             (int)( ( resize.getHeight() + 2 * resize.getY() ) / 2 ) - 2,
                                             5,
                                             5 );
     public void componentHidden(ComponentEvent e)
     public void componentMoved(ComponentEvent e)
     public void componentResized(ComponentEvent e)
          this.setBounds();
     public void componentShown(ComponentEvent e)
     public void setEnabled( boolean enable )
          enabled = enable;
     public boolean isEnabled()
          return enabled;
     public void paint( Graphics g )
          ( (Graphics2D)g ).fillRect( 0, 0, 5, 5 );
}

Answer 1

Hi bbritta,
Thanks for the time. I guess the setLocation MIGHT be off, tho ideally, it should place the tv somewhere near the right bottom corner of the screen.
The basic requirement I have is in the code written. This is what I want. When I start my application, I want the small tv screen only to appear, with the two colored panels (that shall obviously contain some other code). When my mouse hovers on this small screen, the buttons should appear in a panel just below the small screen. So I have used a JLayered pane that displays two separate gifs, one for the small screen, and one for the buttons panel. On the small screen gif, I have added two panels to layer 1, and on the button panel gif, I have added 3 buttons.
What is happening is that if I set the frame size to the size of the small screen at startup (before show()), then on mouse hover, the frame size increases, but the layered pane size stays the same, and hence i cannot see the button panel. But if I start out with the button panel showing (frame size initially set to the larger value), then on mouse exit, the button panel disappears, and reappears properly on mouse enter. But I don't want to set the original size to the larger value, since only the small screen must be seen first.
Did I make my self clear? The whole problem is that on mouse hover, u cannot see the button panel, till u change the setSize() code in initializeFrame() to use c_o_FULL_TV_SIZE instead of c_o_TV_SIZE. That u cannot see the buttons IS my problem!
Thanks,
Shefali.