Java 图形不起作用？

Question

我正在尝试使用youtube教程制作游戏，目前正在尝试创建并填充窗口大小的矩形。它不是变黑，而是保持灰色(我的默认颜色(。

有什么想法吗？提前感谢！

法典：

import javax.swing.*;
import java.awt.image.BufferStrategy;
import java.awt.*;
public class Game extends Canvas implements Runnable {
    private static final long serialVersionUID = 1L;
    public static int width = 300;
    public static int height = width / 16 * 9;
    public static int scale = 3;
    private Thread thread;
    private JFrame frame; // Creates a window
    private boolean running = false; // Checks to see if the game is running
    public Game() {
        Dimension size = new Dimension(width * scale, height * scale); // The window size
        setPreferredSize(size); // Choosing the size I want
        frame = new JFrame(); // Calling the frame
    }
    public synchronized void start() {
        running = true;
        thread = new Thread(new Game(), "Display"); // Calling the class
        thread.start(); // Starting the class
    }
    public synchronized void stop() { // Ending the game
        running = false;
        try {
            thread.join();
        } catch(InterruptedException e) {
            e.printStackTrace();
        }
    }
    public void run() {
        while(running) {
            update();
            render();
        }
    }
    public void update() {
    }
    public void render() {
        BufferStrategy bs = getBufferStrategy();
        if(bs == null) {
            createBufferStrategy(3); // Triple buffering strategy (speeds up process)
            return;
        }
        Graphics g = bs.getDrawGraphics(); // Create a link between buffer and drawing on screen
        g.setColor(Color.BLACK);
        g.fillRect(0, 0, getWidth(), getHeight());
        g.dispose();
        bs.show();
    }
    public static void main(String[] args) {
        Game game = new Game(); // Calling the class to be able to change things in it
        game.frame.setResizable(true); // Stopping window changing in size (causes graphical errors)
        game.frame.setTitle("Game Window");
        game.frame.add(game); // Fills the window with the class (can be done because of 'Canvas')
        game.frame.pack(); // Sets the size of the window based on what is in the component above.
        game.frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        game.frame.setLocationRelativeTo(null); // Centres the window in the screen
        game.frame.setVisible(true);
        game.start(); // Starts the game
    }
}

Answer 1

将thread = new Thread(new Game(), "Display");更改为使用 this 而不是 new Game() 。