程序在Thread.sleep()和Timer期间冻结

Original question:

最初的问题:

This method is supposed to change the image being displayed on a JFrame gradually into another image. However, without some way to slow it down, it just seems to change from one image to the new image. In order to slow it down, I put in a Thread.sleep(1000) so the changes wouldn't happen instantly. However, with this line in there, my program freezes completely. No error message, no nothing. Can anyone please help me out? Suggest a better method to slow it down, or how this can be fixed.

这个方法应该是将一个JFrame中显示的图像逐渐转换成另一个图像。然而，如果没有什么方法来降低它的速度，它就会从一个图像变成新的图像。为了降低速度，我添加了一个Thread.sleep(1000)，这样就不会立即发生更改。但是，有了这条线，我的程序就完全冻结了。没有错误消息，什么都没有。谁能帮我一下吗?建议一种更好的方法来减缓它，或者如何修复它。

For clarification: int k is the number of gradual steps in the change. k = 1 would be an instant change. Anything greater would be gradual changes. int l meanwhile controls the ratio of how much of each image is displayed.

澄清一下:int k是变化中逐渐增加的步数。k = 1是一个瞬间的改变。任何更大的变化都是渐进的。同时，int l控制每个图像显示的比例。

public void morphImg(int width, int height, BufferedImage morphImage, int k) {
    //creates new image from two images of same size
    BufferedImage image2 = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
    for (int i = 0; i < width; i++) {
        for (int j = 0; j < height; j++) {
            //get color from original image
            Color c = new Color(image.getRGB(i, j));

            //get colors from morph image
            Color c2 = new Color(morphImage.getRGB(i, j));

            for (int l = 1; l <= k; l++) {
                //gets colors at different stages
                int r = ((k-l)*c.getRed()/k) + (l*c2.getRed()/k);
                int g = ((k-l)*c.getGreen()/k) + (l*c2.getGreen()/k);
                int b = ((k-l)*c.getBlue()/k) + (l*c2.getBlue()/k);   
                Color newColor = new Color(r, g, b);
                //set colors of new image to average of the two images
                image2.setRGB(i, j, newColor.getRGB());

                //display new image
                try {
                    imageLabel.setIcon(new ImageIcon(image2));
                    Thread.sleep(1000);
                }
                catch (InterruptedException e){
                    System.out.println("Exception caught.");
                }
            }
        }
    }

    //sets modified image as "original" for further manipulation
    setImage(image2);
}

UPDATED CODE: Using a Timer also causes the program to freeze...Am I not using it right?

更新代码:使用计时器也会导致程序冻结……我用错了吗?

public void morphImg(int width, int height, BufferedImage morphImage, int k) {
    //creates new image from two images of same size
    final BufferedImage image2 = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
    for (int l = 1; l <= k; l++) {
        for (int i = 0; i < width; i++) {
            for (int j = 0; j < height; j++) {
                //get color from original image
                Color c = new Color(image.getRGB(i, j));

                //get colors from morph image
                Color c2 = new Color(morphImage.getRGB(i, j));

                //gets colors at different stages
                int r = ((k-l)*c.getRed()/k) + (l*c2.getRed()/k);
                int g = ((k-l)*c.getGreen()/k) + (l*c2.getGreen()/k);
                int b = ((k-l)*c.getBlue()/k) + (l*c2.getBlue()/k);   
                Color newColor = new Color(r, g, b);

                //set colors of new image to average of the two images
                image2.setRGB(i, j, newColor.getRGB());
                //display new image

                imageLabel.setIcon(new ImageIcon(image2));
                final Timer t = new Timer(500,null);
                t.setInitialDelay(500);
                t.start();
            }
        }
    }

    //sets modified image as "original" for further manipulation
    setImage(image2);
}

3 个解决方案

#1

Never use Thread.sleep() when code is executing on the Event Dispatch Thread.

当代码在事件分派线程上执行时，不要使用Thread.sleep()。

Instead you should use a Swing Timer to schedule your animation.

相反，您应该使用Swing定时器来调度您的动画。

See the sections from the Swing tutorial on:

请参阅Swing教程的部分:

1. Concurrency in Swing
2. 并发性在摇摆
3. How to Use Timers
4. 如何使用定时器

Or if you don't want to use a Timer, then you can use a SwingWorker (as described in the tutorial on concurrency) and then just publish() the image after you change it. Then you can use a Thread.sleep() since the SwingWorker doesn't execute on the EDT.

或者，如果您不想使用计时器，那么您可以使用一个SwingWorker(如关于并发的教程中所述)，然后在您更改它之后只发布()映像。然后可以使用Thread.sleep()，因为SwingWorker不会在EDT上执行。

Simple Timer example:

简单计时器的例子:

import java.awt.*;
import java.awt.event.*;
import java.util.*;
import javax.swing.*;

public class TimerTime extends JFrame implements ActionListener
{
    JLabel timeLabel;

    public TimerTime()
    {
        timeLabel = new JLabel( new Date().toString() );
        getContentPane().add(timeLabel, BorderLayout.NORTH);
    }

    public void actionPerformed(ActionEvent e)
    {
        timeLabel.setText( new Date().toString() );
    }

    public static void main(String[] args)
    {
        TimerTime frame = new TimerTime();
        frame.setDefaultCloseOperation( EXIT_ON_CLOSE );
        frame.pack();
        frame.setVisible(true);

        int time = 1000;
        javax.swing.Timer timer = new javax.swing.Timer(time, frame);
        timer.setInitialDelay(1);
        timer.start();
    }
}

#2

The loop over k should be the outermost loop. Right now you are calling Thread.sleep k*width*height times.

k上的循环应该是最外层的循环。现在您正在调用Thread。睡眠k *宽*高*。

#3

If the intention is to show progressive animation of the morph effect, below is the test code I did without using Timer or Thread.sleep(), using the latest morph code given by OP:

如果目的是显示变形效果的渐进动画，下面是我在没有使用Timer或Thread.sleep()的情况下所做的测试代码，使用OP给出的最新变形代码:

import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;

import javax.imageio.ImageIO;
import javax.swing.JApplet;
import javax.swing.JFrame;


class MorphComponent extends Component {

    /**
     * 
     */
    private static final long serialVersionUID = 1L;
    private BufferedImage bi;
    private URL imageSrc1;
    private URL imageSrc2;     
    public MorphComponent(URL imageSrc1, URL imageSrc2) {
        this.imageSrc1 = imageSrc1;
        this.imageSrc2 = imageSrc2;     
        try {
            BufferedImage img1 = ImageIO.read(imageSrc1);
            //BufferedImage img2 = ImageIO.read(imageSrc2);
            int w = img1.getWidth(null);
            int h = img1.getHeight(null);
            bi = new BufferedImage(w, h, BufferedImage.TYPE_INT_ARGB);
            Graphics g = bi.getGraphics();
            g.drawImage(img1, 0, 0, null);

        } catch (IOException e) {
            System.out.println("Image could not be read");
            System.exit(1);
        }
    }

    public Dimension getPreferredSize() {
        return new Dimension(bi.getWidth(null), bi.getHeight(null));
    }


    public void paint(Graphics g) {
        Graphics2D g2d = (Graphics2D)g;
        g2d.setColor(Color.white);
        g2d.fillRect(0,0, getWidth(), getHeight());
        try {
            BufferedImage img1 = ImageIO.read(imageSrc1);
            BufferedImage img2 = ImageIO.read(imageSrc2);
            int w = img1.getWidth(null);
            int h = img1.getHeight(null);        
            bi = morphImg(g, img1, img2, w, h, 10);
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

    private long start = System.currentTimeMillis();

    public BufferedImage morphImg(Graphics gp, BufferedImage originalImage, BufferedImage morphImage, int width, int height, int k) {
        //creates new image from two images of same size
        final BufferedImage image2 = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
        for (int l = 1; l <= k; l++) {
            for (int i = 0; i < width; i++) {
                for (int j = 0; j < height; j++) {
                    long elapsed = System.currentTimeMillis() - start;
                    //get color from original image
                    Color c = new Color(originalImage.getRGB(i, j));

                    //get colors from morph image
                    Color c2 = new Color(morphImage.getRGB(i, j));

                    //gets colors at different stages
                    int r = ((k-l)*c.getRed()/k) + (l*c2.getRed()/k);
                    int g = ((k-l)*c.getGreen()/k) + (l*c2.getGreen()/k);
                    int b = ((k-l)*c.getBlue()/k) + (l*c2.getBlue()/k);   
                    Color newColor = new Color(r, g, b);

                    //set colors of new image to average of the two images
                    image2.setRGB(i, j, newColor.getRGB());

                    if( elapsed > 100 ) {
                        gp.drawImage(image2, 0, 0, null);
                        start = System.currentTimeMillis();
                        repaint();
                    }

                }
            }
        }
        return image2;
    }

}

public class MorphImageApplet extends JApplet {

    /**
     * 
     */
    private static final long serialVersionUID = 1L;
    static String imageFileName1 = "image_1.jpg";
    static String imageFileName2 = "image_2.jpg";
    private URL imageSrc1;
    private URL imageSrc2;

    public MorphImageApplet () {
    }

    public MorphImageApplet (URL imageSrc1, URL imageSrc2) {
        this.imageSrc1 = imageSrc1;
        this.imageSrc2 = imageSrc2;
    }

    public void init() {
        try {
            imageSrc1 = new URL(getCodeBase(), imageFileName1);
            imageSrc2 = new URL(getCodeBase(), imageFileName2);
        } catch (MalformedURLException e) {
        }
        buildUI();
    }

    public void buildUI() {
        final MorphComponent st = new MorphComponent(imageSrc1, imageSrc2);
        add("Center", st);
    }

    public static void main(String s[]) {
        JFrame f = new JFrame("See Through Image");
        f.addWindowListener(new WindowAdapter() {
            public void windowClosing(WindowEvent e) {System.exit(0);}
        });
        URL imageSrc1 = null;
        URL imageSrc2 = null;
        try {
             imageSrc1 = ((new File(imageFileName1)).toURI()).toURL();
             imageSrc2 = ((new File(imageFileName2)).toURI()).toURL();
        } catch (MalformedURLException e) {
        }
        MorphImageApplet sta = new MorphImageApplet(imageSrc1, imageSrc2);
        sta.buildUI();
        f.add("Center", sta);
        f.pack();
        f.setVisible(true);
    }
}