java - 小程序图像丢失

Question

Stackoverflow 成员(member)们大家好，

CatchTheCreature Applet 类应该显示在不同位置通过时间延迟重新绘制的图像，但由于某种原因该图像未显示。

  import java.awt.Color;
  import java.awt.Graphics;
  import java.awt.event.ActionEvent;
  import java.awt.event.ActionListener;
  import java.awt.event.MouseEvent;
  import java.awt.event.MouseListener;
  import java.util.Random;

  import javax.swing.ImageIcon;
  import javax.swing.JApplet;
  import javax.swing.Timer;

  public class CatchTheCreature extends JApplet {

private int height = 300;
private int width = 600;
private final int delay = 1001;

private ImageIcon image;
private Timer timer;
private int x, y;
private int counter = 0;
Random gn = new Random();

public void init() {
    DotListener dot = new DotListener();
    addMouseListener(dot);

    image = new ImageIcon("Monster.png");

    timer = new Timer(delay, new timerListener());
    x = 40;
    y = 40;
    getContentPane().setBackground(Color.black);

}

// Action Listener Methods
private class timerListener implements ActionListener {
    public void actionPerformed(ActionEvent e) {

        x = gn.nextInt(width);
        y = gn.nextInt(height);

        repaint();
    }

}

private class DotListener implements MouseListener {

    public void mousePressed(MouseEvent event) {

    }

    @Override
    public void mouseClicked(MouseEvent event) {
        if (event.getX() > (x) && event.getX() < (x + 60)
                && event.getY() < (y + 60) && event.getY() > (y)) {
            x = gn.nextInt(width);
            y = gn.nextInt(height);
            counter = counter + 1;
            repaint();
        }
    }

    @Override
    public void mouseEntered(MouseEvent event) {

    }

    @Override
    public void mouseExited(MouseEvent event) {

    }

    @Override
    public void mouseReleased(MouseEvent event) {

    }

}

public void paint(Graphics g) {
    super.paint(g);
    g.setColor(Color.yellow);
    image.paintIcon(this, g, x, y);
    g.drawString("Clicked accuratly: " + counter, 5, 15);
}

public void start() {
    timer.start();

}

public void stop() {
    timer.stop();
}

}

这是我的 html 文件

     <applet code = CatchTheCreature width = 250 height = 300>

     </applet>

如果有人能告诉我如何在小程序上显示图像图标，我将非常感激。

谢谢

Answer 1

..image = new ImageIcon("Monster.png");

• ImageIcon 的基于 String 的构造函数假定 String 代表一个File。
• 沙盒小程序无法访问 File 对象，但可以访问来自同一代码库/文档库的 URL。
• 使用 getDocumentBase()/getCodeBase() 以及图像的相对路径，小程序将是可移植的(假设图像也上传到同一位置) )。