Question

所以我对Java很新，我使用tutorial为蛇游戏构建了这个Board。它似乎工作得很好，除了图像文件不会加载。我之前没有使用Eclipse中的图像，所以我不知道自己在做什么。我尝试将.png图像文件放在包中，但这根本没有帮助。我很感激任何想法。

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Image;
import java.awt.Graphics;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;

import javax.swing.ImageIcon;
import javax.swing.JPanel;
import javax.swing.Timer;

public class Board extends JPanel implements ActionListener {

/**
 * 
 */
private static final long serialVersionUID = 1L;
private final int B_WIDTH = 300;
private final int B_HEIGHT = 300;
private final int DOT_SIZE = 10;
private final int ALL_DOTS = 900;
private final int  RAND_POS = 29;
private final int DELAY = 140;

private final int x[] = new int[ALL_DOTS];
private final int y[] = new int[ALL_DOTS];

private int dots;
private int apple_x;
private int apple_y;

private boolean leftDirection = false;
private boolean rightDirection = true;
private boolean upDirection = false;
private boolean downDirection = false;
private boolean inGame = true;

private Timer timer;
private Image ball;
private Image apple;
private Image head;

public Board() {
    addKeyListener(new TAdapter());
    setBackground(Color.black);
    setFocusable(true);

    setPreferredSize(new Dimension(B_WIDTH, B_HEIGHT));
    loadImages();
    initGame();
    }

private void loadImages() {

    ImageIcon iid = new ImageIcon("dot.png");
    ball = iid.getImage();

    ImageIcon iia = new ImageIcon("apple.png");
    apple = iia.getImage();

    ImageIcon iih = new ImageIcon("head.png");
    head = iih.getImage();
}

private void initGame() {

    dots = 3;

    for (int z = 0; z < dots; z++) {
        x[z] = 50 - z * 10;
        y[z] = 50;
    }

    locateApple();

    timer = new Timer(DELAY, this);
    timer.start();
}

@Override
public void paintComponent(Graphics g) {
    super.paintComponent(g);

    doDrawing(g);
}

private void doDrawing(Graphics g) {

    if (inGame) {

        g.drawImage(apple, apple_x, apple_y, this);

        for (int z = 0; z < dots; z++) {
            if (z == 0) {
                g.drawImage(head, x[z], y[z], this);
            } else {
                g.drawImage(ball, x[z], y[z], this);
            }
        }

        Toolkit.getDefaultToolkit().sync();
    } else {

        gameOver(g);
    }
}

private void gameOver (Graphics g) {

    String msg = "Game Over";
    Font small = new Font ("Helvetica", Font.BOLD, 14);
    FontMetrics metr = getFontMetrics(small);

    g.setColor(Color.white);
    g.setFont(small);
    g.drawString(msg, (B_WIDTH - metr.stringWidth(msg)) / 2, B_HEIGHT / 2);

}

private void checkApple(){

    if ((x[0] == apple_x) && (y[0] == apple_y)) {

        dots++;
        locateApple();
    }
}

private void move() {

    for (int z = dots; z > 0; z--) {

        x[z] = x[(z - 1)];
        y[z] = y[(z - 1)];
    }

    if (leftDirection) {
        x[0] -= DOT_SIZE;
    }

    if (rightDirection) {
        x[0] += DOT_SIZE;
    }

    if (upDirection) {
        y[0] -= DOT_SIZE;
    }

    if (downDirection) {
        y[0] += DOT_SIZE;
    }
}

private void checkCollision(){

    for (int z = dots; z > 0; z--) {

        if ((z > 4) && (x[0] == x[z]) && (y[0] == y[z])) {


        }
    }

   if (y[0] >= B_HEIGHT) {
            inGame = false;
        }

        if (y[0] < 0) {
            inGame = false;
        }

        if (x[0] >= B_WIDTH) {
            inGame = false;
        }

        if (x[0] < 0) {
            inGame = false;
        }

        if(!inGame) {
            timer.stop();
        }
}


private void locateApple() {

    int r = (int) (Math.random() * RAND_POS);
    apple_x = ((r * DOT_SIZE));

    r = (int) (Math.random() * RAND_POS);
    apple_y = ((r * DOT_SIZE));
}

@Override
public void actionPerformed(ActionEvent e) {

    if (inGame) {

        checkApple();
        checkCollision();
        move();
    }

    repaint();
}

private class TAdapter extends KeyAdapter {

    @Override
    public void keyPressed(KeyEvent e) {

        int key = e.getKeyCode();

        if ((key == KeyEvent.VK_LEFT) && (!rightDirection)) {
            leftDirection = true;
            upDirection = false;
            downDirection = false;
        }

        if ((key == KeyEvent.VK_RIGHT) && (!leftDirection)) {
            rightDirection = true;
            upDirection = false;
            downDirection = false;
        }

        if ((key == KeyEvent.VK_UP) && (!downDirection)) {
            upDirection = true;
            rightDirection = false;
            leftDirection = false;
        }

        if ((key == KeyEvent.VK_DOWN) && (!upDirection)) {
            downDirection = true;
            rightDirection = false;
            leftDirection = false;
        }
    }
}

}

Answer 1

Use ImageIO instead.

如果您需要ImageIcon，请从通过ImageIO加载的图像中创建一个。在这种情况下，游戏甚至不使用Icon，所以不要打扰，只需使用ImageIO加载BufferedImage。

重载

ImageIO.read()以接受File，InputStream或URL。所以你的文件需要定位取决于你如何使用它。尝试将图像放在特定位置并使用绝对路径进行测试：

private void loadImages() {
    ball = ImageIO.read(new File("c:/img/dot.png"));
}

完成上述工作之后，您可以参考File或ClassLoader.getResource()周围文档的加载位置的一般文档。

我不使用Eclipse但是我怀疑你可能想要：

将图像文件放入与Board类相同的包中。
使用getClass().getResourceAsStream(...)获取InputStream。
将流转换为图像。

类似的东西：

public void loadImages() {
    ball = ImageIO.read(getClass().getResourceAsStream("dot.png"));
}

ImageIO还可以在加载失败时为您提供更多有用的例外。

Answer 2

我尝试将.png图像文件放在包
中

我建议不要将图像文件放在与源文件相同的包中。实际上，源文件夹的公共层次结构如下所示：

src/main/java
src/main/resources
src/test/java
src/test/resources

在src / main / java源文件夹中，您可以拥有源文件的不同包。对于src / test / java也是如此，除了它们是测试文件。

在src / main / resources中，您可以放置包含所有资源文件的文件夹（i18n文件，图像等）。这些文件夹可以从构建路径中排除，也不需要是源文件夹。

例如：

然后，您应该能够：

public static void main(String... args) {
    final ImageIcon imageIcon = new ImageIcon("src/main/resources/Desert.jpg");
}

图像文件不会加载到2D Java游戏中

2 个答案: