一旦被另一个类调用，Java图形将不适用于JPanel类

Question

我创建了一个计算器，该计算器应该在按下某些键时提示您进行Pong游戏。 我的乒乓球游戏是单独创建的，本身运行良好。 但是，一旦在我的Calculator程序中实现了图形，图形将拒绝移动。

下面是Calculator程序中的KeyAdapter代码，它将提示Pong游戏：

 import java.applet.Applet;
 import java.awt.List;
 import java.awt.event.KeyAdapter;
 import java.awt.event.KeyEvent;
 import java.awt.event.KeyListener;
 import java.util.ArrayList;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 import javax.swing.JFrame;

 public class Konami extends KeyAdapter {

private ArrayList<Integer> keys  = new ArrayList<Integer>();
private ArrayList<Integer> keysMarked  = new ArrayList< >();


public ArrayList init(){

    keysMarked.add(KeyEvent.VK_UP);
    keysMarked.add(KeyEvent.VK_UP);
    keysMarked.add(KeyEvent.VK_DOWN);
    keysMarked.add(KeyEvent.VK_DOWN);
    keysMarked.add(KeyEvent.VK_LEFT);
    keysMarked.add(KeyEvent.VK_RIGHT);
    keysMarked.add(KeyEvent.VK_LEFT);
    keysMarked.add(KeyEvent.VK_RIGHT);
    keysMarked.add(KeyEvent.VK_B);
    keysMarked.add(KeyEvent.VK_A);

    return keysMarked;
}




@Override
public void keyTyped(KeyEvent event) {

}


@Override
public void keyPressed(KeyEvent event) {

    Konami pong = new Konami();

                keys.add(event.getKeyCode());

                if (keys.size() == keysMarked.size()){
                     if (keys.equals(keysMarked)){
                         System.out.println("PONG GAME");

 //Here I call the Pong game:

                         JFrame newFrame = new JFrame();
                         Pong game = new Pong();
                         game.setVisible(true);
                         newFrame.setBounds(450, 170, 400, 300);
                         newFrame.setResizable(false);
                         newFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                         newFrame.add(game);

                         newFrame.setVisible(true);

                      } 
                     else 
                         keys.clear();
                }
                else if (keys.size() > keysMarked.size())
                {
                    keys.clear();
                }
}

@Override
public void keyReleased(KeyEvent event) {
}


}

这是Pong游戏的代码：

 package cs1302.calc;
 import java.awt.BorderLayout;
 import java.awt.Color;
 import java.awt.Dimension;
 import java.util.logging.*;
 import java.awt.Graphics;
 import java.awt.event.KeyEvent;
 import static java.lang.Math.abs;
 import javax.swing.JFrame;
 import javax.swing.JPanel;
 import javax.swing.JTextArea;
 import javax.swing.JTextField;

  public class Pong extends JPanel{
int x = 0;
int y = 0;

static int xP = 0;
static int yP = 150;

static int xP2 = 390;
static int yP2 = 150;

int border = 30;
boolean ballGoingDown = true;
boolean ballGoingRight = true;

private void moveBall(){

    if (ballGoingRight == true){
        x = x + 1;
    }

    if (ballGoingRight == false){
        x = x - 1;
    }


    if (ballGoingDown == true){
        y = y + 1;
    }

    if (ballGoingDown == false){
        y = y - 1;
    }

    //detects hit bottom
    if (y== getHeight() - border){
        ballGoingDown = false;
    }

    if (y== 0){
        ballGoingDown = true;
    }


    //detects hit bat
    if (abs(x-xP) <3  &&  abs(y-yP) <30 ){
        ballGoingRight = true;
    }

    if (abs(x-xP2) <23  &&  abs(y-yP2) <30 ){
        ballGoingRight = false;
    }

    //detects ball moving past border
    if (x < 0){
        System.out.println("PLAYER 2 WINS.");
        System.exit(0);
    };

    if (x > getWidth()){
        System.out.println("PLAYER 1 WINS.");
        System.exit(0);
    };

}

private void moveBat(){
    Control c = new Control();


}


@Override
public void paint(Graphics g){
    super.paint(g);
    g.setColor(Color.ORANGE);
    g.fillOval(x, y, 30, 30);

    g.setColor(Color.BLUE);
    g.fillRect(xP, yP, 10,30);


    g.setColor(Color.BLUE);
    g.fillRect(xP2, yP2, 10,30);



}




public static void main2(String s) throws InterruptedException{
        //My window code
       JFrame myFrame = new JFrame("pong");


        myFrame.setBounds(450, 170, 400, 300);
        myFrame.setResizable(false);
       myFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

       //My game code
       Pong game = new Pong();
       myFrame.add(game);

       game.setFocusable(true);
       game.requestFocusInWindow();
       Control control = new Control();
       game.addKeyListener(control);


       new BorderLayout();
       JTextArea textArea = new JTextArea("Player 1: S Key (up) Z Key(down)"
               + "| Player 2: Up(up) Down (down)");
       game.add(textArea, BorderLayout.PAGE_END);

       myFrame.setVisible(true);


       while (true)
       {
           game.moveBall();
           game.repaint();

           Thread.sleep(10);
       }


}

}

最后是KeyAdapter类，用于控制Pong游戏中的图形：

 import java.awt.Graphics;
 import java.awt.event.KeyAdapter;
 import java.awt.event.KeyEvent;
 import javax.swing.JFrame;
 import javax.swing.JPanel;
 import cs1302.calc.Pong;

  public class Control extends KeyAdapter {

@Override
public void keyTyped(KeyEvent event) {

}

@Override
 public void keyPressed(KeyEvent event) {
      if (event.getKeyCode() == KeyEvent.VK_S){  

          Pong.yP = Pong.yP - 25;
      }
       if (event.getKeyCode() == KeyEvent.VK_Z){        
          Pong.yP = Pong.yP + 25;

      }

        if (event.getKeyCode() == KeyEvent.VK_UP){  
          Pong.yP2 = Pong.yP2 - 25;
      }
       if (event.getKeyCode() == KeyEvent.VK_DOWN){        
          Pong.yP2 = Pong.yP2 + 25;

      }
}

  @Override
public void keyReleased(KeyEvent event) {
}
 }

Answer 1

当您从KeyListener初始化Pong ，负责动画的代码根本不会运行，因为它位于Pong.main2() ，并且您不会调用该代码。 但是，不要简单地这样称呼，因为这种方法还有其他问题：

如果从事件分派线程之外的其他任何地方调用Pong.main() ，就像它在正常运行时必须执行的操作一样，则Pong类将在EDT外部错误地初始化其UI。 它还在EDT外部（在主线程中）运行游戏循环。 后来的错误使它起作用。

从KeyListener启动时，如果调用Pong.main()或以相同方式实现游戏循环的任何其他方法，则它将阻塞EDT，并且不会进行绘制。 而不是循环，应使用回转计时器来处理图形和更新。 这不会阻塞事件分发线程，并且在需要运行时也可以在EDT中正确运行相关代码。