addKeyListener（）不适用于JPanel

简而言之，您的面板需要专注。在创建面板的任何地方添加：

panel.setFocusable(true);panel.requestFocusInWindow();

这是一个SSCCE（我建议以后再问其中一个问题）：

import java.awt.Dimension;import java.awt.event.KeyEvent;import java.awt.event.KeyListener;import javax.swing.Jframe;import javax.swing.JPanel;import javax.swing.SwingUtilities;public class SimpleKeyTest {    public static void main(String[] args) {        Runnable r = new Runnable() { @Override public void run() {     Jframe frame = new Jframe();     JPanel panel = new JPanel();     frame.getContentPane().add(panel);     panel.addKeyListener(new KeyListener() {         @Override         public void keyTyped(KeyEvent e) {}         @Override         public void keyReleased(KeyEvent e) {}         @Override         public void keyPressed(KeyEvent e) {  System.out.println("Pressed " + e.getKeyChar());         }     });     panel.setFocusable(true);     panel.requestFocusInWindow();     frame.setSize(new Dimension(300, 300));     frame.setVisible(true); }        };        SwingUtilities.invokeLater(r);    }}

另外，https：//www.google.com/search？q = jpanel +
keylistener