animationpanel.java

java编程开发技巧与实例的编译测试通过的所有例程

import java.awt.MediaTracker;
import java.awt.Dimension;
import java.awt.Image;
import java.awt.BorderLayout;
import java.awt.Graphics;
import javax.swing.*;

public class AnimationPanel extends JPanel implements Runnable
{
	private Image images[]	=	new Image[9];
	private int	currentImage	=	0;
	private Thread thread = null;
	public AnimationPanel()
	{
		MediaTracker tracker	=	new MediaTracker(this);
		for (int i = 0; i < images.length; i ++)
		{
			images[i] = getToolkit().getImage("smile" + i + ".gif");
			tracker.addImage(images[i], i);
		}
		try
		{
			tracker.waitForAll();
		}
		catch	(InterruptedException ie)
		{
			showError("Image loading interrupted: " + ie);
		}
		if (tracker.isErrorAny())
			showError("Error loading one or more images");
		thread	=	new Thread(this);
		thread.start();
	}
	public void run()
	{
		while (true)
		{
			try
			{
				repaint();
				thread.sleep(100);
				if	(currentImage >= images.length - 1)
					currentImage = 0;
				else
					currentImage ++;
			}
			catch	(InterruptedException ie)
			{
				showError("Thread interrupted: " + ie);
			}
		}
	}
	public Dimension getPreferredSize()
	{
		return new Dimension(images[0].getWidth(this), images[0].getHeight(this));
	}
	public void paintComponenet(Graphics g)
	{
		super.paintComponent(g);
		g.drawImage(images[currentImage], 0, 0, this);
	}
	private void showError(String msg)
	{
		JOptionPane.showMessageDialog(this, msg, "Error", JOptionPane.ERROR_MESSAGE);
	}
}