java - 图像未显示在 Canvas 上(Java)

Question

我正在创建一个游戏，但背景和主角未加载。这是我声明变量的地方:

private BufferedImage background;   
private BufferedImage player;

这是我获取图像的地方:

try {
    background = ImageIO.read(this.getClass().getResourceAsStream("/res/Background.jpg"));
    player = ImageIO.read(this.getClass().getResourceAsStream("/res/Player.jpg"));
} catch (IOException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
}

这是我的渲染方法:

public void render() {
    BufferStrategy bs = this.getBufferStrategy();

    if (bs == null) {
        createBufferStrategy(3);
        return;
    }

    Graphics g = bs.getDrawGraphics();

    g.drawImage(background, 0, 0, this);
    g.drawImage(player, 0, 0, this);

    g.dispose();
    bs.show();
}

这是我的全类同学:

public class Main extends Canvas implements Runnable, KeyListener {

    Thread t;
    boolean running = false;

    private BufferedImage background;

    private BufferedImage player;

    public Main() {

        setFocusable(true);
        requestFocus();
        addKeyListener(this);

        try {
            background = ImageIO.read(this.getClass().getResourceAsStream("/res/Background.jpg"));
            player = ImageIO.read(this.getClass().getResourceAsStream("/res/Player.jpg"));
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }

    @Override
    public void run() {

        while (running) {
            tick();
            render();
        }

        stop();

    }

    synchronized void start() {

        if (running) return;
        running = true;

        Thread t = new Thread();
    t.start();

}

synchronized void stop() {
    try {
        t.join();
    } catch (InterruptedException e) {
        e.printStackTrace();
    }

    System.exit(0);
}

public void render() {
    BufferStrategy bs = this.getBufferStrategy();

    if (bs == null) {
        createBufferStrategy(3);
        return;
    }

    Graphics g = bs.getDrawGraphics();

    g.drawImage(background, 0, 0, this);
    g.drawImage(player, 0, 0, this);

    g.dispose();
    bs.show();
}

public void tick() {

}

@Override
public void keyPressed(KeyEvent e) {
    int code = e.getKeyCode();

    if (code == KeyEvent.VK_ESCAPE) {
        System.exit(0);
    }
}

@Override
public void keyReleased(KeyEvent e) {
    // TODO Auto-generated method stub

}

@Override
public void keyTyped(KeyEvent e) {
    // TODO Auto-generated method stub

}

public static void main(String[] args) {
    JFrame f = new JFrame("Mission Sahara");
    Main m = new Main();

    f.add(m);
    f.setExtendedState(JFrame.MAXIMIZED_BOTH);
    f.setUndecorated(true);
    f.setResizable(false);
    f.setVisible(true);
    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    m.start();
}

}

我的代码有什么问题吗？

Answer 1

您正在 start 方法中创建一个“空”Thread...

Thread t = new Thread();
t.start();

这不会做很多事情。

相反，您可能想做一些类似的事情......

synchronized void start() {

    if (running) {
        return;
    }
    running = true;

    Thread t = new Thread(this);
    t.start();

}

因为Main实现了Runnable