Java Graphics方法drawImage不能使用'this'作为ImageObserver我该怎么办？

Question

我对java编程很新，只是遵循关于用Java编写小游戏的指南。所以我必须使用Graphics类中的drawImage方法绘制一个Image。我已经覆盖了paint方法，并尝试调用g.drawImage（myImage / 类图像实例 /，character.getX，character.get，this）。现在Eclipse说我需要一个ImageObserver，我认为是正确的，但我想当我覆盖该方法并将Argument作为图形实例（此处命名为g）类时，这是g的引用，这是我的ImageObserver。

package Game;

import java.applet.Applet;
import java.awt.Color;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.awt.image.ImageObserver;
import java.awt.Frame;
import java.net.URL;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.image.ImageObserver;

public class MainGame extends Applet implements Runnable, KeyListener {

public final static int width = 800;
public final static int height = 400;

private Bird bird;
private Image image,character;
private URL base;
private Graphics second;



public static int getwidth() {
    return width;
}
public static int getheight() {
    return height;
}

@Override
public void init() {
    // TODO Auto-generated method stub
    super.init();
    setSize(width, height);
    setBackground(Color.BLACK);
    setFocusable(true);
    addKeyListener(this);
    Frame frame = (Frame) this.getParent().getParent();
    frame.setTitle("MyApplet");

    try {
        base = getDocumentBase();
    } catch (Exception e) {
        // TODO: handle exception
    }
    //Path of your Image
    character = getImage(base, "path to .png image (removed)");
}

@Override
public void start() {
    // TODO Auto-generated method stub
    super.start();
    Thread thread = new Thread(this);
    thread.start();
}

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

}

@Override
public void keyPressed(KeyEvent e) {
    // TODO Auto-generated method stub
    switch(e.getKeyCode()) {
    case KeyEvent.VK_UP:
        bird.resetSpeed();
        break;
    case KeyEvent.VK_KP_DOWN:
        System.out.println("Do nothing");
        break;
    case KeyEvent.VK_SPACE:
        bird.resetSpeed();
        break;
    }

}

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

}

@Override
public void run() {
    // TODO Auto-generated method stub
    while(true) {
        repaint();
        bird.update();
        try{Thread.sleep(17);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}

@Override
public void update(Graphics g) {
    // TODO Auto-generated method stub
    super.update(g);
    if (image == null) {
        image = createImage(this.getWidth(), this.getHeight());
        second = image.getGraphics();
    }

    second.setColor(getBackground());
    second.fillRect(0, 0, getWidth(), getHeight());
    second.setColor(getForeground());
    paint(second);

    g.drawImage(image, 0, 0, this);
}


@Override
public void paint(Graphics g) {
    // TODO Auto-generated method stub
    g.drawImage(character, bird.getCenterX(), bird.getCenterY(), null );
}

public static void main(String[] args) {
    // TODO Auto-generated method stub

}

}