Java-图片直到循环结束才显示？

Question

In Java, I have successfully displayed an image on the screen. Now I want to make it move by running it through a for loop. The for loop runs 10 times and sleeps for 1 second each time. Instead of moving the image every second as expected, I have to wait 10 seconds, then 10 images show up.

Here's my code:

import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Toolkit;

import javax.swing.JComponent;
import javax.swing.JFrame;

public class ImageDraw extends JComponent {
    public void paint(Graphics g) {
        Graphics2D g2 = (Graphics2D) g;
        Image img1 = Toolkit.getDefaultToolkit().getImage("player.png");

        int x = 0;
        int y = 0;

        for(int i = 0;i<10;i++){
            try {
                Thread.sleep(1000);
                x+=10;
                y+=10;
                g2.drawImage(img1, x, y, this);
                repaint();
            } catch (InterruptedException e) {
                e.printStackTrace();
                System.exit(0);
            }   
        }   //end for

    }   //end paint

}   //end class

How would I make it so the image looks as if it's moving everytime it runs through the loop?

Answer 1

In addition to other suggestions:

1. Never read the image in the painting method. Read the image when you construct the class or pass in the image with a setImage(...) method.

2. Custom painting is done by overriding the paintComponent() method, not the paint() method.

Answer 2

Use a Timer for this, and get rid of the Thread.sleep() . You're running this code on the UI thread, and when you call Thread.sleep() you're putting the UI thread to sleep, which means no updating until the entire loop is complete.