Java-Pong AI不动

Question

我在用java做乒乓球，但是敌人AI没有移动。它应该向球指向的方向移动。有人能帮帮我吗？

主修班：

import javax.swing.*;

public class Main extends JFrame{
    final static int WW = 800;
    final static int WH = 600;
    public Main(){
        setSize(WW,WH);
        setResizable(false);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setLocationRelativeTo(null);
        setTitle("Pong");
        add(new GamePanel());
        setVisible(true);
    }
    public static void main(String[] args){
        new Main();
    }
}

GamePanel类：

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class GamePanel extends JPanel implements ActionListener,KeyListener{
    Player player = new Player();
    Computer computer = new Computer();
    Ball ball = new Ball();

public GamePanel(){
    Timer time = new Timer(20, this);
    time.start();
    this.addKeyListener(this);
    this.setFocusable(true);
}

private void update(){
    player.update();
    ball.update();
    ball.Collision(player);
    computer.update();
    ball.Collision(computer);
}

public void paintComponent(Graphics g){
    g.setColor(Color.BLACK);
    g.fillRect(0, 0, Main.WW, Main.WH);
    player.paint(g);
    ball.paint(g);
    computer.paint(g);
}
public void actionPerformed(ActionEvent e){
    update();
    repaint();
}
public void keyPressed(KeyEvent e){
    if(e.getKeyCode() == KeyEvent.VK_UP){
        player.setyv(-10);
    }
    else if(e.getKeyCode() == KeyEvent.VK_DOWN){
        player.setyv(10);
    }
}
public void keyReleased(KeyEvent e){
    if(e.getKeyCode()==KeyEvent.VK_UP || e.getKeyCode()==KeyEvent.VK_DOWN)
        player.setyv(0);
}
public void keyTyped(KeyEvent e){

}

}

球员班：

import java.awt.*;

public class Player {
    private int y = 300;
    private int w = 20;
    private int h = 120;
    private int yv = 0;
    private int x = 700;

    public Player(){
    }

    public void update(){
        y = y + yv;
    }

    public void paint(Graphics g){
        g.setColor(Color.WHITE);
        g.fillRect(x,y,w,h);
    }

    public void setyv(int speed){
        yv = speed;
    }
    public int getX(){
        return this.x;
    }
    public int getY(){
        return this.y;
    }
    public int getW(){
        return this.w;
    }
    public int getH(){
        return this.h;
    }
}

球类：

import java.awt.*;

public class Ball {
    private int x = 400;
    private int y = 300;
    private int xv = -10;
    private int yv = 10;

    public void update(){
        x = x += xv;
        y = y += yv;
        if(x < 10){
            xv = 10;
        }
        if(x > 770){
            xv = -10;
        }
        if(y < 10){
            yv = 5;
        }
        if(y > 550){
            yv = -5;
        }
    }
    public int getY(){
        return this.y;
    }
    public void paint(Graphics g){
        g.setColor(Color.WHITE);
        g.fillOval(x, y, 20, 20);
    }
    public void Collision(Player player){
        if(this.x > (player.getX()-10)){
            if(this.y > player.getY() && (this.y < player.getY() + player.getH())){
                xv = -10;
            }
        }
    }
    public void Collision(Computer cpu){
        if(this.x < (cpu.getX()+10)){
            if(this.y > cpu.getY() && (this.y < cpu.getY() + cpu.getH())){
                xv = 10;
            }
        }
    }
}

电脑课：

import java.awt.*;

public class Computer {
    private int y = 300;
    private int w = 20;
    private int h = 120;
    private int yv = 0;
    private int x = 100;
    Ball ballpos = new Ball();

    public Computer(){
    }

    public void update(){
        if(ballpos.getY() < this.y){
            yv = -1;
        }
        else if(ballpos.getY() > this.y){
            yv = 1;
        }
        y = y + yv;
    }

    public void paint(Graphics g){
        g.setColor(Color.WHITE);
        g.fillRect(x,y,w,h);
    }
    public int getX(){
        return this.x;
    }
    public int getY(){
        return this.y;
    }
    public int getW(){
        return this.w;
    }
    public int getH(){
        return this.h;
    }
}

很抱歉，如果这是太多的代码，但如果只发送AI类，你看不出问题在哪里，我猜。请帮帮我，我不知道它为什么不起作用。对不起我的英语不好。

Answer 1

您的计算机类创建一个不同的球(球)，从来没有更新，因此AI从不移动。需要将Ball对象从GamePanel类传递给Computers update方法：

电脑：

public void update(Ball ball){
    if(ball.getY() < this.y){
        yv = -1;
    }
    else if(ball.getY() > this.y){
        yv = 1;
    }
    y = y + yv;
}

GamePanel：

private void update(){
    player.update();
    ball.update();
    ball.Collision(player);
    computer.update(ball);
    ball.Collision(computer);
}