我有一个方法JPanel
private void paintScore(Graphics2D g) {
Font scoreFont = new Font("Arial", Font.PLAIN, 72);
g.setFont(scoreFont);
FontMetrics scoreFontMetrics = g.getFontMetrics();
g.drawString("" + playerOneScore, SCREEN_WIDTH / 2 - 30
- scoreFontMetrics.stringWidth("" + playerOneScore),
SCREEN_HEIGHT / 2);
g.drawString("" + playerTwoScore, SCREEN_WIDTH / 2 + 30,
SCREEN_HEIGHT / 2);
}
当我调用此方法时,它似乎第一次起作用。然后,在那之后它再也不会起作用了。
如果我注释掉该方法的调用,它始终有效。
但是,如果我调用JFrame's revalidate()
方法,该程序也始终有效。
我不确定这里发生了什么。
如果需要,我可以发布完整的源代码。
提前致谢
这是其余的代码。
主 JPanel 扩展类。
import java.awt.Color;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionListener;
import java.awt.image.BufferedImage;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class GamePanel extends JPanel implements Runnable, MouseMotionListener {
private static final int SCREEN_WIDTH = 640;
private static final int SCREEN_HEIGHT = 480;
private static final int INDENT = 20;
private int playerOneScore = 0;
private int playerTwoScore = 0;
private ImageEntity playerOne = new ImageEntity("Images/bouncer.bmp");
private ImageEntity playerTwo = new ImageEntity("Images/bouncer.bmp");
private int mouseX = 0;
private int mouseY = 0;
private BufferedImage gameScreen = new BufferedImage(SCREEN_WIDTH,
SCREEN_HEIGHT, BufferedImage.TYPE_INT_RGB);
Graphics2D gameScreenGraphics = gameScreen.createGraphics();
public GamePanel() throws Exception {
paintBackground(gameScreenGraphics);
paintScore(gameScreenGraphics);
paintBouncers(gameScreenGraphics);
}
public void run() {
}
public void mouseMoved(MouseEvent m) {
mouseX = m.getXOnScreen();
mouseY = m.getYOnScreen();
}
public void mouseDragged(MouseEvent m) {
}
public void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(gameScreen, 0, 0, this);
}
private void paintBackground(Graphics2D g) {
g.setColor(Color.BLACK);
g.fillRect(0, 0, SCREEN_WIDTH, SCREEN_HEIGHT);
g.setColor(Color.WHITE);
for (int i = 0; i < 10; i++) {
g.fillRect(SCREEN_WIDTH / 2 - 5, i * SCREEN_HEIGHT / 10, 10,
(SCREEN_HEIGHT / 10) - 10);
}
}
private void paintScore(Graphics2D g) {
Font scoreFont = new Font("Arial", Font.PLAIN, 72);
g.setFont(scoreFont);
FontMetrics scoreFontMetrics = g.getFontMetrics();
g.drawString("" + playerOneScore, SCREEN_WIDTH / 2 - 30
- scoreFontMetrics.stringWidth("" + playerOneScore),
SCREEN_HEIGHT / 2);
g.drawString("" + playerTwoScore, SCREEN_WIDTH / 2 + 30,
SCREEN_HEIGHT / 2);
}
private void paintBouncers(Graphics2D g) {
g.drawImage(playerOne.getImage(), playerOne.getX(), playerOne.getY(),
this);
g.drawImage(playerTwo.getImage(), playerTwo.getX(), playerTwo.getY(),
this);
}
public static void main(String[] args)throws Exception {
JFrame mainPane = new JFrame("Pong - Mrinank Sharma");
mainPane.setSize(SCREEN_WIDTH, SCREEN_HEIGHT);
mainPane.setVisible(true);
mainPane.setResizable(false);
GamePanel gp = new GamePanel();
mainPane.add(gp);
mainPane.revalidate();
}
}
ImageEntity 是一个类,它只是 BufferedImage 的包装器。
再次感谢各位