Question

我制作了这段代码，当你启动它时它会显示一个图像然后当你按下左或右键时在其他两个图像之间进行更改，但由于某种原因它不是从键盘读取输入，我尝试使用mouseListener，它工作，这是代码：

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.Toolkit;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JPanel;

public class Implementary extends JFrame
{
    private static final long serialVersionUID = 1L;
    public Dimension d;
    public static ImageIcon Im = new ImageIcon(Implementary.class.getResource("death.png"));
    public static ImageIcon Imc = new ImageIcon(Implementary.class.getResource("right.png"));
    public static ImageIcon I = new ImageIcon(Implementary.class.getResource("left.png"));
    public static Image Img = Im.getImage();
    public static int x = 10;
    public static int y = 10;

    public Implementary()
    {
        super("hue");
        int x1 = (int) Toolkit.getDefaultToolkit().getScreenSize().getWidth();
        int y1 = (int) Toolkit.getDefaultToolkit().getScreenSize().getHeight();
        d = new Dimension(x1, y1 - 45);
        this.setSize(d);
        this.setLocationRelativeTo(null);
        Panel p = new Panel();
        p.addKeyListener(new KeyListener()
        {
            @Override
            public void keyTyped(KeyEvent e)
            {
                keyPressed(e);
            }

            @Override
            public void keyPressed(KeyEvent e)
            {
                int k = e.getKeyCode();
                if (k == KeyEvent.VK_LEFT)
                {
                    Img = I.getImage();
                    repaint();
                    System.out.println(3);
                }
                else
                {
                    Img = Imc.getImage();
                    repaint();
                    System.out.println(2);
                }
                System.out.println(1);
            }

            @Override
            public void keyReleased(KeyEvent e)
            {
                keyPressed(e);
            }
        });
        this.add(p);
    }

    static class Panel extends JPanel
    {
        private static final long serialVersionUID = 1L;

        public void paintComponent(Graphics g)
        {
            super.paintComponent(g);
            this.setBackground(Color.cyan);
            g.drawImage(Img, x, y, null);
        }
    }
}

这是主要的课程：

public class Yo
{
    public static void main(String args[])
    {
        Implementary imp = new Implementary();
        imp.setVisible(true);
    }
}

Answer 1

将KeyListener添加到整个JFrame可以解决问题。由于您的JPanel无法选择/聚焦，因此无法接收击键。

更改

p.addKeyListener(new KeyListener()

到

this.addKeyListener(new KeyListener()

适合我。

关键听众因某种原因无法工作

1 个答案: