package myWidgets;

//======================================================================
//  PROJECT:            _programming.java_
//  FILE:               WordPro.java
//  PURPOSE:            Chapter 11 lablet
//  VERSION:            2.0
//  TARGET:             Java v1.1
//  UPDATE HISTORY:     2.0     12/4/98    1.1 event model
//                      1.0     7/28/97    the version in _p.j_
//======================================================================

//------------------------------ IMPORTS -------------------------------
	
import java.awt.*;
 
//======================= AnimatedButton CLASS =========================
/**
 * This class implements an animated version of GraphicButton.
 * images[0] is the down picture--the rest are for the animated up state.
 * Requires at least three images for animation.
 */
public class AnimatedButton extends GraphicButton implements Runnable
{
    private long    delayTime;
    private Thread  myThread;
    private boolean goingDown = false;
	
    //------------------------ Constructors ----------------------------
    
    public AnimatedButton(Image[] imgs, String label, long delayMs)
    {
        super(imgs, label);
        delayTime = delayMs;
        myThread = new Thread(this);
        myThread.start();
    }
	
    public AnimatedButton(Image[] imgs, long delayMs)
    {
        this(imgs, null, delayMs);
    }
    
    //---------------------- Thread handlers ---------------------------
    
    /**
     * Start the animation thread.
     */
    public void start()
    {
        if (myThread == null)
        {
            myThread = new Thread(this);
            myThread.start();
        }
    }
	
    /**
     * Cycle through the up pictures when needed.
     */
    public void run()
    {
        while (myThread != null)
        {
            try
            {
                Thread.sleep(delayTime);
            }
            catch (InterruptedException e)
            { }
            
            // Do nothing this turn if this button is down or if
            // no animation is possible.
            if ((curImage == 0) || (theImage.length == 2))
            {
                continue;
            }
            
            if (goingDown)
            {
                if (curImage == 1)
                {
                    curImage++;
                    goingDown = false; 
                }
                else
                {
                    curImage--;
                }
            }
            else
            {
                if (curImage == theImage.length - 1)
                {
                    curImage--;
                    goingDown = true; 
                }
                else
                {
                    curImage++;
                }
            }        
            repaint();
        }
    }
    
    /**
     * Stop the animation thread.
     */
    public void stop()
    {
        if ((myThread != null) && myThread.isAlive())
        {
            myThread.stop();
        }
        myThread = null;
    }
}