java - 当x和y位置进入另一个位置时如何执行操作？

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我正在尝试制作一个有趣的小赛车游戏。到目前为止，我有两个成功移动的矩形，并且我有一个 map 设置供它们竞速通过。我的 map 也是由矩形组成的。之前我犯了一个错误，没有给我的两个赛车手一个具体的客观名称。所以它们只是移动的两个位置。现在我想做的是，让矩形墙实际上成为墙，这样它们就不会只是穿过它们。我听说如果我把墙做成阵列(不知道如何)，我就可以掩盖我的错误，这样它们就不会穿过它们。它是否正确？还有其他方法可以做到这一点吗？到目前为止，情况如下:

谢谢，这是我的代码。第一类是框架和黑色矩形的信息。第二类是蓝色矩形和墙壁的信息。

头等舱:

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;

public class MyGame extends JPanel implements ActionListener, KeyListener {
    Timer t = new Timer(5, this);
    int x = 0, y = 0, velx =0, vely =0, g = 0;
    private Color color;

    public MyGame() {
        t.start();
        addKeyListener(this);
        setFocusable(true);
        setFocusTraversalKeysEnabled(false);
    }

    @Override
    public Dimension getPreferredSize() {
        return new Dimension(1300, 750);
    }

    @Override
    public void paintComponent(Graphics g) {
        super.paintComponent(g);
        g.setColor(color);
        g.fillRect(x, y, 50, 30);

    }


    @Override
    public void actionPerformed(ActionEvent e) {
        if (x < 0) //stops us from going backwards past x = 0
        {
            velx = 0;
            x = 0;
        }

        if (y < 0) //stops us from going to the sky
        {
            vely = 0;
            y = 0;
        }

        if (y > 725) // stops us from going through the ground
        {
            vely = 0;
            y = 725;
        }
        if (x > 1250) // stops us from going through the wall
        {
            velx = 0;
            x = 1250;
        }

        x += velx;
        y += vely;
        repaint();
    }

    @Override
    public void keyPressed(KeyEvent e) {
        int code = e.getKeyCode();

        {
            if (code == KeyEvent.VK_DOWN) {
                vely = 2; // removing velx = 0 allows us to go vertically and horizontlly at the same time
                velx = 0;
            }
            if (code == KeyEvent.VK_UP) {
                vely = -2; // same goes for here
                velx = 0;
            }
            if (code == KeyEvent.VK_LEFT) {
                vely = 0;
                velx = -2;
            }

            {
                if (code == KeyEvent.VK_RIGHT) {
                    vely = 0;
                    velx = 2;

                }
            }
        }
    }

    @Override
    public void keyTyped(KeyEvent e) {
    }

    @Override
    public void keyReleased(KeyEvent e) {

    }




    public static void main (String arge[]){

        JFrame frame = new JFrame("Testing");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setLayout(new BorderLayout());
        frame.add(new Incoming());           
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);

    }
}

二等:

import java.awt.Color;
import java.awt.Graphics;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;


public class Incoming extends MyGame {

private Color color;



int x = 0, y = 0; 
int velx = 0, vely = 0;

public Incoming() {
    color = Color.BLUE;
    Rectangle rect = new Rectangle();


}

@Override
public void paintComponent(Graphics g) {


    super.paintComponent(g);
    g.setColor(color);
    g.fillRect(x, y, 50, 30);

    g.setColor(Color.blue);        

    g.drawRect(0, 100, 80, 30);
    g.drawRect(80, 100, 80, 30);
    g.drawRect(160, 100, 80, 30);
    g.drawRect(240, 100, 80, 30);
    g.drawRect(320, 100, 80, 30);
    g.drawRect(400, 100, 80, 30);
    g.drawRect(480, 100, 80, 30);
    g.drawRect(560, 100, 80, 30);
    g.drawRect(640, 100, 80, 30);
    g.drawRect(720, 100, 80, 30);
    g.drawRect(800, 100, 80, 30);
    g.drawRect(880, 100, 80, 30);
    g.drawRect(960, 100, 80, 30);
    g.drawRect(1040, 100, 80, 30);

    g.drawRect(1040, 250, 80, 30);
    g.drawRect(1120, 250, 80, 30);
    g.drawRect(1200, 250, 80, 30);
    g.drawRect(960, 250, 80, 30);
    g.drawRect(880, 250, 80, 30);
    g.drawRect(800, 250, 80, 30);
    g.drawRect(720, 250, 80, 30);
    g.drawRect(640, 250, 80, 30);
    g.drawRect(560, 250, 80, 30);
    g.drawRect(480, 250, 80, 30);
    g.drawRect(400, 250, 80, 30);
    g.drawRect(320, 250, 80, 30);
    g.drawRect(240, 250, 80, 30);
    g.drawRect(160, 250, 80, 30);

    g.drawRect(1040, 400, 80, 30);
    g.drawRect(960, 400, 80, 30);
    g.drawRect(880, 400, 80, 30);
    g.drawRect(800, 400, 80, 30);
    g.drawRect(720, 400, 80, 30);
    g.drawRect(640, 400, 80, 30);
    g.drawRect(560, 400, 80, 30);
    g.drawRect(480, 400, 80, 30);
    g.drawRect(400, 400, 80, 30);
    g.drawRect(320, 400, 80, 30);
    g.drawRect(240, 400, 80, 30);
    g.drawRect(160, 400, 80, 30);
    g.drawRect(80, 400, 80, 30);
    g.drawRect(0, 400, 80, 30);

    g.drawRect(1040, 550, 80, 30);       
    g.drawRect(1120, 550, 80, 30);
    g.drawRect(1200, 550, 80, 30);
    g.drawRect(960, 550, 80, 30);
    g.drawRect(880, 550, 80, 30);
    g.drawRect(800, 550, 80, 30);
    g.drawRect(720, 550, 80, 30);
    g.drawRect(640, 550, 80, 30);
    g.drawRect(560, 550, 80, 30);
    g.drawRect(480, 550, 80, 30);
    g.drawRect(400, 550, 80, 30);
    g.drawRect(320, 550, 80, 30);
    g.drawRect(240, 550, 80, 30);
    g.drawRect(160, 550, 80, 30);

    g.drawRect(1040, 550, 80, 30);
    g.drawRect(960, 550, 80, 30);
    g.drawRect(880, 550, 80, 30);
    g.drawRect(800, 550, 80, 30);
    g.drawRect(720, 550, 80, 30);
    g.drawRect(640, 550, 80, 30);
    g.drawRect(560, 550, 80, 30);
    g.drawRect(480, 550, 80, 30);
    g.drawRect(400, 550, 80, 30);
    g.drawRect(320, 550, 80, 30);
    g.drawRect(240, 550, 80, 30);
    g.drawRect(160, 550, 80, 30);



}

@Override
public void actionPerformed(ActionEvent e) {
    super.actionPerformed(e);
    if (x < 0) //stops us from going backwards past x = 0
    {
        velx = 0;
        x = 0;
    }

    if (y < 0) //stops us from going to the sky
    {
        vely = 0;
        y = 0;
    }

    if (y > 725) // stops us from going through the ground
    {
        vely = 0;
        y = 725;
    }

    if (x > 1250) // stops us from going through the wall
    {
        velx = 0;
        x = 1250;
    }

    if (y < 0.1)        
    {

        y = 50;
    }

    x += velx;
    y += vely;
    repaint();
}

@Override
public void keyPressed(KeyEvent e) {
    super.keyPressed(e);
    int code = e.getKeyCode();

    {
        if (code == KeyEvent.VK_S) {
            vely = 2; // removing velx = 0 allows us to go vertically and horizontlly at the same time
            velx = 0;
        }
        if (code == KeyEvent.VK_W) {
            vely = -2; // same goes for here
            velx = 0;
        }
        if (code == KeyEvent.VK_A) {
            vely = 0;
            velx = -2;
        }

        {
            if (code == KeyEvent.VK_D) {
                vely = 0;
                velx = 2;

            }
        }
    }
}

@Override
public void keyReleased(KeyEvent e) {
    super.keyReleased(e);

}
}

Answer 1

How would I list rectangles?

请参阅 Custom Painting Approaches 中的 DrawOnCompnent 示例。它向您展示了如何从 ArrayList 进行绘制。