java - 形状未绘制在正确的位置，在其他位置绘制 20-40 像素(使用 MouseListener)

Question

当我尝试在鼠标单击的位置绘制类似正方形的东西时，该正方形会在距离鼠标单击几个像素的地方绘制。不仅如此，当窗口第一次打开时，它似乎并没有显示为 1080 x 720(黑色背景实际上被遮挡，你必须调整窗口大小)，这可能与此有关吗？

我尝试比较鼠标点击的位置和方 block 的位置，但它们是相同的。单击某个点会使方 block 移动到那里...或者它应该...(在 Windows 10 上运行)。如有任何帮助，我们将不胜感激，谢谢。

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

public class Core extends JComponent implements MouseListener, ActionListener
{
private Timer timer;
private Player player;


public Core()
{
    timer = new Timer(3, this);
    timer.start();
    player = new Player(500, 500, 30, 30, 1);
}

public static void main(String[] args)
{
    JFrame window = new JFrame();
    Core game = new Core();
    window.add(game);
    window.addMouseListener(game);
    window.pack();
    window.setSize(1080, 720);
    window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    window.setVisible(true);
}

public void paintComponent(Graphics g)
{
    Graphics2D g2 = (Graphics2D) g;
    g2.fillRect(0,0,1080,720);

    if(timer.isRunning())
        player.paint(g2);


}


@Override
public void mouseClicked(MouseEvent e)
{

     player.setNewPosition(e.getX(), e.getY());


}

@Override
public void mousePressed(MouseEvent e)
{

}

@Override
public void mouseReleased(MouseEvent e)
{

}

@Override
public void mouseEntered(MouseEvent e)
{

}

@Override
public void mouseExited(MouseEvent e)
{

}

@Override
public void actionPerformed(ActionEvent e)
{
    repaint();
}
}

<小时/>

import java.awt.*;

public class Player
{
private int x,y,width,length,speed;
private int newX, newY;

public Player(int x, int y, int width, int length, int speed)
{
    this.x = x;
    this.y = y;
    this.width = width;
    this.length = length;
    this.speed = speed;
    newX = x;
    newY = y;
}

public void setNewPosition(int newX, int newY)
{
    this.newX = newX;
    this.newY = newY;
}

public void move()
{
    if(x > newX)
        x -= speed;
    else if(x < newX)
        x += speed;
    if(y > newY)
        y -= speed;
    else if(y < newY)
        y += speed;
}


public void paint(Graphics2D g2) //paint method
{
    g2.setColor(Color.blue);
    move();
    g2.fillRect(x, y, width, length);
}
}

Answer 1

改变

public static void main(String[] args)
{
    JFrame window = new JFrame();
    Core game = new Core();
    window.add(game);
    window.addMouseListener(game);
    window.pack();
    window.setSize(1080, 720);
    window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    window.setVisible(true);
}

更像是......

public static void main(String[] args)
{
    EventQueue.invokeLater(new Runnable() {
        public void run() {
            JFrame window = new JFrame();
            Core game = new Core();
            game.addMouseListener(game);
            window.add(game);
            window.pack();
            window.setSize(1080, 720);
            window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            window.setVisible(true);
        }
    });
}

MouseEvent 使用的坐标将相对于源 的坐标空间

就个人而言，我会在 Core 的构造函数中注册 MouseListener，但您明白了