gcc/libjava/classpath/javax/swing/plaf/basic/BasicProgressBarUI.java

/* BasicProgressBarUI.java --
   Copyright (C) 2004, 2005  Free Software Foundation, Inc.

This file is part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
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02110-1301 USA.

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permission to link this library with independent modules to produce an
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package javax.swing.plaf.basic;

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.Insets;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.Shape;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ComponentAdapter;
import java.awt.event.ComponentEvent;
import java.awt.event.ComponentListener;
import java.awt.geom.AffineTransform;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;

import javax.swing.JComponent;
import javax.swing.JProgressBar;
import javax.swing.LookAndFeel;
import javax.swing.SwingConstants;
import javax.swing.SwingUtilities;
import javax.swing.Timer;
import javax.swing.UIManager;
import javax.swing.event.AncestorEvent;
import javax.swing.event.AncestorListener;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
import javax.swing.plaf.ComponentUI;
import javax.swing.plaf.ProgressBarUI;

/**
 * The Basic Look and Feel UI delegate for the 
 * JProgressBar.
 */
public class BasicProgressBarUI extends ProgressBarUI
{
  /**
   * A helper class that listens for ChangeEvents 
   * from the progressBar's model.
   *
   * @specnote Apparently this class was intended to be protected,
   *           but was made public by a compiler bug and is now
   *           public for compatibility.
   */
  public class ChangeHandler implements ChangeListener
  {
    /**
     * Called every time the state of the model changes.
     *
     * @param e The ChangeEvent given by the model.
     */
    public void stateChanged(ChangeEvent e)
    {
      // Nothing to do but repaint.
      progressBar.repaint();
    }
  }

  /**
   * This helper class is used to listen for 
   * PropertyChangeEvents from the progressBar.
   */
  private class PropertyChangeHandler implements PropertyChangeListener
  {
    /**
     * Called every time the properties of the 
     * progressBar change.
     *
     * @param e The PropertyChangeEvent given by the progressBar.
     */
    public void propertyChange(PropertyChangeEvent e)
    {
      // Only need to listen for indeterminate changes.
      // All other things are done on a repaint.
      if (e.getPropertyName().equals("indeterminate"))
        if (((Boolean) e.getNewValue()).booleanValue()
            && progressBar.isShowing())
          startAnimationTimer();
        else
          stopAnimationTimer();
    }
  }

  /**
   * Receives notification when the progressbar is becoming visible or
   * invisible and starts/stops the animation timer accordingly.
   *
   * @author Roman Kennke (kennke@aicas.com)
   */
  private class AncestorHandler implements AncestorListener
  {

    /**
     * Receives notification when the progressbar is becoming visible. This
     * starts the animation timer if the progressbar is indeterminate.
     *
     * @param event the ancestor event
     */
    public void ancestorAdded(AncestorEvent event)
    {
      if (progressBar.isIndeterminate())
        startAnimationTimer();
    }

    /**
     * Receives notification when the progressbar is becoming invisible. This
     * stops the animation timer if the progressbar is indeterminate.
     *
     * @param event the ancestor event
     */
    public void ancestorRemoved(AncestorEvent event)
    {
      stopAnimationTimer();
    }

    /**
     * Receives notification when an ancestor has been moved. We don't need to
     * do anything here.
     */
    public void ancestorMoved(AncestorEvent event)
    {
      // Nothing to do here.
    }
    
  }

  /**
   * This helper class is used to listen for 
   * the animationTimer's intervals. On every interval,
   * the bouncing box should move.
   */
  private class Animator implements ActionListener
  {
    /**
     * Called every time the animationTimer reaches
     * its interval.
     *
     * @param e The ActionEvent given by the timer.
     */
    public void actionPerformed(ActionEvent e)
    {
      // Incrementing the animation index will cause
      // a repaint.
      incrementAnimationIndex();
    }
  }

  /**
   * Receives notification when the size of the progress bar changes and
   * invalidates the layout information for the box calculation in
   * {@link BasicProgressBarUI#getBox(Rectangle)}.
   *
   * @author Roman Kennke (kennke@aicas.com)
   */
  private class ComponentHandler extends ComponentAdapter
  {
    /**
     * Receives notification when the size of the progress bar changes and
     * invalidates the layout information for the box calculation in
     * {@link BasicProgressBarUI#getBox}.
     *
     * @param e the component event
     */
    public void componentResized(ComponentEvent e)
    {
      boxDependent = -1;
      boxIndependent = -1;
      incr = -1;
    }
  }

  /**
   * Holds the value of the bouncing box that is returned by {@link #getBox}.
   *
   * @since 1.5
   */ 
  protected Rectangle boxRect;

  /** The timer used to move the bouncing box. */
  private transient Timer animationTimer;

  // The total number of frames must be an even number.
  // The total number of frames is calculated from
  // the cycleTime and repaintInterval given by
  // the basic Look and Feel defaults.
  //
  // +-----------------------------------------------+
  // | frame0 | frame1 | frame2 | frame 3 | frame 4  |
  // |        | frame7 | frame6 | frame 5 |          |
  // +-----------------------------------------------+
  
  /** The current animation index. */
  private transient int animationIndex;

  /** The total number of frames.*/
  private transient int numFrames;

  /** The helper that moves the bouncing box. */
  private transient Animator animation;

  /** The helper that listens for property change events. */
  private transient PropertyChangeHandler propertyListener;

  /** The Listener for the model. */
  protected ChangeListener changeListener;

  /** The progressBar for this UI. */
  protected JProgressBar progressBar;


  /**
   * The size of the box returned by {@link #getBox} in the orientation
   * direction of the progress bar. This is package private to avoid accessor
   * method.
   */
  transient double boxDependent = - 1;

  /**
   * The size of the box returned by {@link #getBox} against the orientation
   * direction of the progress bar. This is package private to avoid accessor
   * method. 
   */
  transient int boxIndependent = - 1;

  /**
   * The increment for box animation. This is package private to avoid accessor
   * method.
   */
  transient double incr = -1;

  /** The length of the cell. The cell is the painted part. */
  private transient int cellLength;

  /** The gap between cells. */
  private transient int cellSpacing;

  /** The color of the text when the bar is not over it.*/
  private transient Color selectionBackground;

  /** The color of the text when the bar is over it. */
  private transient Color selectionForeground;

  /**
   * Listens for notification when the component becomes showing and
   * starts/stops the animation timer.
   */
  private AncestorListener ancestorListener;

  /**
   * Listens for resize events on the progress bar and invalidates some
   * layout info.
   */
  private ComponentListener componentListener;

  /**
   * Creates a new BasicProgressBarUI object.
   */
  public BasicProgressBarUI()
  {
    super();
  }

  /**
   * Creates a new BasicProgressBarUI for the component.
   *
   * @param x The JComponent to create the UI for.
   *
   * @return A new BasicProgressBarUI.
   */
  public static ComponentUI createUI(JComponent x)
  {
    return new BasicProgressBarUI();
  }

  /**
   * This method returns the length of the bar (from the minimum)
   * in pixels (or units that the Graphics object draws in) based
   * on the progressBar's getPercentComplete() value.
   *
   * @param b The insets of the progressBar.
   * @param width The width of the progressBar.
   * @param height The height of the progressBar.
   *
   * @return The length of the bar that should be painted in pixels.
   */
  protected int getAmountFull(Insets b, int width, int height)
  {
    double percentDone = progressBar.getPercentComplete();
    if (progressBar.getOrientation() == JProgressBar.HORIZONTAL)
      return (int) (percentDone * (width - b.left - b.right));
    else
      return (int) (percentDone * (height - b.top - b.bottom));
  }

  /**
   * The current animation index.
   *
   * @return The current animation index.
   */
  protected int getAnimationIndex()
  {
    return animationIndex;
  }

  /**
   * This method returns the size and position of the bouncing box
   * for the current animation index. It stores the values in the 
   * given rectangle and returns it. It returns null if no box should
   * be drawn.
   *
   * @param r The bouncing box rectangle.
   *
   * @return The bouncing box rectangle.
   */
  protected Rectangle getBox(Rectangle r)
  {
    if (!progressBar.isIndeterminate())
      return null;
    if (r == null)
      r = new Rectangle();

    Rectangle vr = new Rectangle();
    SwingUtilities.calculateInnerArea(progressBar, vr);

    // Recalculate the metrics only when size of the progressbar has changed.
    if (incr == -1 || boxDependent == -1 || boxIndependent == -1)
      {
        //numFrames has to be an even number as defined by spec.
        int iterations = numFrames / 2;
        if (progressBar.getOrientation() == JProgressBar.HORIZONTAL)
          {
            boxDependent = vr.width / 6.;
            incr = ((double) (vr.width - boxDependent)) / (double) iterations;
            boxIndependent = vr.height;
          }
        else
          {
            boxDependent = vr.height / 6.;
            incr = ((double) (vr.height - boxDependent)) / (double) iterations;
            boxIndependent = vr.width;
          }
      }

    int index = getAnimationIndex();
    if (animationIndex > numFrames / 2)
      index = numFrames - getAnimationIndex();

    if (progressBar.getOrientation() == JProgressBar.HORIZONTAL)
      {
        r.x = vr.x + (int) (incr * index);
        r.y = vr.y;
        r.width = (int) boxDependent;
        r.height = (int) boxIndependent;
      }
    else
      {
        r.x = vr.x;
        r.y = vr.height - (int) (incr * index) + vr.y - (int) boxDependent;
        r.width = (int) boxIndependent;
        r.height = (int) boxDependent;
      }
    return r;
  }

  /**
   * This method returns the length of the cells.
   *
   * @return The cell length.
   */
  protected int getCellLength()
  {
    return cellLength;
  }

  /**
   * This method returns the spacing between cells.
   *
   * @return The cell gap.
   */
  protected int getCellSpacing()
  {
    return cellSpacing;
  }

  /**
   * This method returns the maximum size of the JComponent.
   * If it returns null, it is up to the LayoutManager
   * to give it a size.
   *
   * @param c The component to find a maximum size for.
   *
   * @return The maximum size.
   */
  public Dimension getMaximumSize(JComponent c)
  {
    Insets insets = c.getInsets();
    Dimension ret;
    int orientation = progressBar.getOrientation();
    if (orientation == JProgressBar.VERTICAL)
      {
        ret = getPreferredInnerVertical();
        ret.height = Short.MAX_VALUE;
        ret.width += insets.left + insets.right;
      }
    else
      {
        ret = getPreferredInnerHorizontal();
        ret.width = Short.MAX_VALUE;
        ret.height += insets.top + insets.bottom;
      }
    return ret;
  }

  /**
   * This method returns the minimum size of the JComponent.
   * If it returns null, it is up to the LayoutManager to
   * give it a size.
   *
   * @param c The component to find a minimum size for.
   *
   * @return The minimum size.
   */
  public Dimension getMinimumSize(JComponent c)
  {
    Insets insets = c.getInsets();
    Dimension ret;
    int orientation = progressBar.getOrientation();
    if (orientation == JProgressBar.VERTICAL)
      {
        ret = getPreferredInnerVertical();
        ret.height = 10;
        ret.width += insets.left + insets.right;
      }
    else
      {
        ret = getPreferredInnerHorizontal();
        ret.width = 10;
        ret.height += insets.top + insets.bottom;
      }
    return ret;
  }

  /**
   * This method returns the preferred size of the inner
   * rectangle (the bounds without the insets) if the
   * progressBar is horizontal.
   *
   * @return The preferred size of the progressBar minus 
   *         insets if it's horizontal.
   */
  protected Dimension getPreferredInnerHorizontal()
  {
    Font font = progressBar.getFont();
    FontMetrics fm = progressBar.getFontMetrics(font);

    int stringWidth = 0;
    String str = progressBar.getString();
    if (str != null)
      stringWidth = fm.stringWidth(progressBar.getString());
    Insets i = progressBar.getInsets();
    int prefWidth = Math.max(200 - i.left - i.right, stringWidth);

    int stringHeight = 0;
    if (str != null)
      stringHeight = fm.getHeight();
    int prefHeight = Math.max(16 - i.top - i.bottom, stringHeight);

    return new Dimension(prefWidth, prefHeight);
  }

  /**
   * This method returns the preferred size of the inner
   * rectangle (the bounds without insets) if the 
   * progressBar is vertical.
   *
   * @return The preferred size of the progressBar minus
   *         insets if it's vertical.
   */
  protected Dimension getPreferredInnerVertical()
  {
    Font font = progressBar.getFont();
    FontMetrics fm = progressBar.getFontMetrics(font);

    int stringWidth = 0;
    String str = progressBar.getString();
    if (str != null)
      stringWidth = fm.stringWidth(progressBar.getString());
    Insets i = progressBar.getInsets();
    int prefHeight = Math.max(200 - i.left - i.right, stringWidth);

    int stringHeight = 0;
    if (str != null)
      stringHeight = fm.getHeight();
    int prefWidth = Math.max(16 - i.top - i.bottom, stringHeight);

    return new Dimension(prefWidth, prefHeight);
  }

  /**
   * This method returns the preferred size of the 
   * given JComponent. If it returns null, then it
   * is up to the LayoutManager to give it a size.
   *
   * @param c The component to find the preferred size for.
   *
   * @return The preferred size of the component.
   */
  public Dimension getPreferredSize(JComponent c)
  {
    Insets insets = c.getInsets();
    Dimension ret;
    int orientation = progressBar.getOrientation();
    if (orientation == JProgressBar.VERTICAL)
      ret = getPreferredInnerVertical();
    else
      ret = getPreferredInnerHorizontal();
    ret.width += insets.left + insets.right;
    ret.height += insets.top + insets.bottom;
    return ret;
  }

  /**
   * This method returns the Color that the text is shown in when the bar is
   * not over the text.
   *
   * @return The color of the text when the bar is not over it.
   */
  protected Color getSelectionBackground()
  {
    return selectionBackground;
  }

  /**
   * This method returns the Color that the text is shown in  when the bar is
   * over the text.
   *
   * @return The color of the text when the bar is over it.
   */
  protected Color getSelectionForeground()
  {
    return selectionForeground;
  }

  /**
   * This method returns the point (the top left of the bounding box)
   * where the text should be painted. 
   *
   * @param g The Graphics object to measure FontMetrics with.
   * @param progressString The string to paint.
   * @param x The x coordinate of the overall bounds box.
   * @param y The y coordinate of the overall bounds box.
   * @param width The width of the overall bounds box.
   * @param height The height of the overall bounds box.
   *
   * @return The top left of the bounding box where text should be painted.
   */
  protected Point getStringPlacement(Graphics g, String progressString, int x,
                                     int y, int width, int height)
  {
    Rectangle tr = new Rectangle();
    Rectangle vr = new Rectangle(x, y, width, height);
    Rectangle ir = new Rectangle();

    Font f = g.getFont();
    FontMetrics fm = g.getFontMetrics(f);

    SwingUtilities.layoutCompoundLabel(progressBar, fm, progressString, null,
                                       SwingConstants.CENTER,
                                       SwingConstants.CENTER,
                                       SwingConstants.CENTER,
                                       SwingConstants.CENTER, vr, ir, tr, 0);
    return new Point(tr.x, tr.y);
  }

  /**
   * This method increments the animation index.
   */
  protected void incrementAnimationIndex()
  {
    animationIndex++;
    //numFrames is like string length, it should be named numFrames or something
    if (animationIndex >= numFrames)
      animationIndex = 0;
    progressBar.repaint();
  }

  /**
   * This method paints the progressBar. It delegates its responsibilities
   * to paintDeterminate and paintIndeterminate.
   *
   * @param g The Graphics object to paint with.
   * @param c The JComponent to paint.
   */
  public void paint(Graphics g, JComponent c)
  {
    if (! progressBar.isIndeterminate())
      paintDeterminate(g, c);
    else
      paintIndeterminate(g, c);
  }

  /**
   * This method is called if the painting to be done is 
   * for a determinate progressBar.
   *
   * @param g The Graphics object to paint with.
   * @param c The JComponent to paint.
   */
  protected void paintDeterminate(Graphics g, JComponent c)
  {
    Color saved = g.getColor();
    int space = getCellSpacing();
    int len = getCellLength();
    int max = progressBar.getMaximum();
    int min = progressBar.getMinimum();
    int value = progressBar.getValue();

    Rectangle vr = SwingUtilities.calculateInnerArea(c, new Rectangle());
    Rectangle or = progressBar.getBounds();
    Insets insets = c.getInsets();

    int amountFull = getAmountFull(insets, or.width, or.height);

	if (progressBar.getOrientation() == JProgressBar.HORIZONTAL)
	  {
	    g.setColor(c.getForeground());
	    g.fillRect(vr.x, vr.y, amountFull, vr.height);
	  }
	else
	  {
	    g.setColor(c.getForeground());
	    g.fillRect(vr.x, vr.y + vr.height - amountFull, vr.width, 
                       amountFull);
	  }

    if (progressBar.isStringPainted() && !progressBar.getString().equals(""))
      paintString(g, 0, 0, or.width, or.height, amountFull, insets);
    g.setColor(saved);
  }

  /**
   * This method is called if the painting to be done is for
   * an indeterminate progressBar.
   *
   * @param g The Graphics object to paint with.
   * @param c The JComponent to paint.
   */
  protected void paintIndeterminate(Graphics g, JComponent c)
  {
    //need to paint the box at it's current position. no text is painted since
    //all we're doing is bouncing back and forth
    Color saved = g.getColor();
    Insets insets = c.getInsets();

    Rectangle or = c.getBounds();
    Rectangle vr = new Rectangle();
    SwingUtilities.calculateInnerArea(c, vr);

    g.setColor(c.getBackground());
    g.fillRect(vr.x, vr.y, vr.width, vr.height);

    boxRect = getBox(boxRect);

    g.setColor(c.getForeground());
    g.fillRect(boxRect.x, boxRect.y, boxRect.width, boxRect.height);

    if (progressBar.isStringPainted() && !progressBar.getString().equals(""))
      paintString(g, 0, 0, or.width, or.height,
                  getAmountFull(insets, or.width, or.height), insets);

    g.setColor(saved);
  }

  /**
   * This method paints the string for the progressBar.
   *
   * @param g The Graphics object to paint with.
   * @param x The x coordinate of the progressBar.
   * @param y The y coordinate of the progressBar.
   * @param width The width of the progressBar.
   * @param height The height of the progressBar.
   * @param amountFull The amount of the progressBar that has its bar filled.
   * @param b The insets of the progressBar.
   */
  protected void paintString(Graphics g, int x, int y, int width, int height,
                             int amountFull, Insets b)
  {
    String str = progressBar.getString();
    int full = getAmountFull(b, width, height);
    Point placement = getStringPlacement(g, progressBar.getString(),
                                         x + b.left, y + b.top, 
                                         width - b.left - b.right,
                                         height - b.top - b.bottom);
    Color savedColor = g.getColor();
    Shape savedClip = g.getClip();
    FontMetrics fm = g.getFontMetrics(progressBar.getFont());
    
    if (progressBar.getOrientation() == JProgressBar.VERTICAL)
      {
        AffineTransform rotate = AffineTransform.getRotateInstance(Math.PI / 2);
        g.setFont(progressBar.getFont().deriveFont(rotate));
      }
    
    g.setColor(getSelectionForeground());
    g.setClip(0, 0, full + b.left, height);
    g.drawString(str, placement.x, placement.y + fm.getAscent());
    g.setColor(getSelectionBackground());
    g.setClip(full + b.left, 0, width - full, height);
    g.drawString(str, placement.x, placement.y + fm.getAscent());
    g.setClip(savedClip);
    g.setColor(savedColor);
  }

  /**
   * This method sets the current animation index. If the index is greater than
   * the number of frames, it resets to 0.
   * 
   * @param newValue The new animation index.
   */
  protected void setAnimationIndex(int newValue)
  {
    animationIndex = (newValue <= numFrames) ? newValue : 0;
    progressBar.repaint();
  }

  /**
   * This method sets the cell length.
   *
   * @param cellLen The cell length.
   */
  protected void setCellLength(int cellLen)
  {
    cellLength = cellLen;
  }

  /**
   * This method sets the cell spacing.
   *
   * @param cellSpace The cell spacing.
   */
  protected void setCellSpacing(int cellSpace)
  {
    cellSpacing = cellSpace;
  }

  /**
   * This method starts the animation timer. It is called
   * when the propertyChangeListener detects that the progressBar
   * has changed to indeterminate mode.
   *
   * @since 1.4
   */
  protected void startAnimationTimer()
  {
    if (animationTimer != null)
      animationTimer.start();
  }

  /**
   * This method stops the animation timer. It is called when
   * the propertyChangeListener detects that the progressBar
   * has changed to determinate mode.
   *
   * @since 1.4
   */
  protected void stopAnimationTimer()
  {
    if (animationTimer != null)
      animationTimer.stop();
    setAnimationIndex(0);
  }

  /**
   * This method changes the settings for the progressBar to
   * the defaults provided by the current Look and Feel.
   */
  protected void installDefaults()
  {
    LookAndFeel.installColorsAndFont(progressBar, "ProgressBar.background",
                                     "ProgressBar.foreground",
                                     "ProgressBar.font");
    LookAndFeel.installBorder(progressBar, "ProgressBar.border");
    progressBar.setOpaque(true);

    selectionForeground = UIManager.getColor("ProgressBar.selectionForeground");
    selectionBackground = UIManager.getColor("ProgressBar.selectionBackground");
    cellLength = UIManager.getInt("ProgressBar.cellLength");
    cellSpacing = UIManager.getInt("ProgressBar.cellSpacing");

    int repaintInterval = UIManager.getInt("ProgressBar.repaintInterval");
    int cycleTime = UIManager.getInt("ProgressBar.cycleTime");

    if (cycleTime % repaintInterval != 0
        && (cycleTime / repaintInterval) % 2 != 0)
      {
	int div = (cycleTime / repaintInterval) + 2;
	div /= 2;
	div *= 2;
	cycleTime = div * repaintInterval;
      }
    setAnimationIndex(0);
    numFrames = cycleTime / repaintInterval;
    animationTimer.setDelay(repaintInterval);
  }

  /**
   * The method uninstalls any defaults that were
   * set by the current Look and Feel.
   */
  protected void uninstallDefaults()
  {
    progressBar.setFont(null);
    progressBar.setForeground(null);
    progressBar.setBackground(null);

    selectionForeground = null;
    selectionBackground = null;
  }

  /**
   * This method registers listeners to all the 
   * components that this UI delegate needs to listen to.
   */
  protected void installListeners()
  {
    changeListener = new ChangeHandler();
    propertyListener = new PropertyChangeHandler();
    animation = new Animator();

    progressBar.addChangeListener(changeListener);
    progressBar.addPropertyChangeListener(propertyListener);
    animationTimer.addActionListener(animation);

    ancestorListener = new AncestorHandler();
    progressBar.addAncestorListener(ancestorListener);

    componentListener = new ComponentHandler();
    progressBar.addComponentListener(componentListener);
  }

  /**
   * This method unregisters listeners to all the 
   * components that were listened to.
   */
  protected void uninstallListeners()
  {
    progressBar.removeChangeListener(changeListener);
    progressBar.removePropertyChangeListener(propertyListener);
    animationTimer.removeActionListener(animation);

    changeListener = null;
    propertyListener = null;
    animation = null;

    if (ancestorListener != null)
      progressBar.removeAncestorListener(ancestorListener);
    ancestorListener = null;

    if (componentListener != null)
      progressBar.removeComponentListener(componentListener);
    componentListener = null;
  }

  /**
   * This method installs the UI for the given JComponent.
   * This includes setting up defaults and listeners as
   * well as initializing any values or objects that
   * the UI may need.
   *
   * @param c The JComponent that is having this UI installed.
   */
  public void installUI(JComponent c)
  {
    super.installUI(c);
    if (c instanceof JProgressBar)
      {
	progressBar = (JProgressBar) c;

	animationTimer = new Timer(200, null);
	animationTimer.setRepeats(true);

	installDefaults();
	installListeners();
      }
    if (progressBar.isIndeterminate())
      startAnimationTimer();
  }

  /**
   * This method removes the UI for the given JComponent.
   * This includes removing any listeners or defaults
   * that the installUI may have set up.
   *
   * @param c The JComponent that is having this UI uninstalled.
   */
  public void uninstallUI(JComponent c)
  {
    super.uninstallUI(c);
    uninstallListeners();
    uninstallDefaults();

    animationTimer = null;
    progressBar = null;
  }

}