实际上，这是您要添加
Window到的内容
Jframe，但重点是
Jframe，因此，当您键入内容
Keyboard时，该内容
Jframe将
KeyListener转到与
Window类无关的内容。因此，为了克服它，你只需要调用
requestFocusInWindow()的
Window类的对象。试试这个代码，我已经对EDT和东西做了一些修改。
import java.awt.*;import java.awt.event.*;import java.awt.geom.Ellipse2D;import javax.swing.*;public class Window extends JPanel { private static Ellipse2D.Double circle; private Jframe frame; public Window() { super(); int width = 400; int height = 400; circle = new Ellipse2D.Double(0.5 * width, 0.9 * height, 0.1 * width, 0.05 * height); } public Dimension getPreferredSize() { return (new Dimension(frame.getWidth(), frame.getHeight())); } @Override protected void paintComponent(Graphics g) { super.paintComponents(g); Graphics2D brush = (Graphics2D) g; int width = getWidth(); int height = getHeight(); g.clearRect(0, 0, width, height); brush.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); brush.draw(circle); } public class MoveCircle implements KeyListener { @Override public void keyPressed(KeyEvent e) { System.out.println("Working on top!"); if (e.getKeyCode() == Event.ENTER) { System.out.println("Working on bottom!"); double newX = circle.x - 1; circle.x = newX; repaint(); } } @Override public void keyReleased(KeyEvent e) { // TODO Auto-generated method stub } @Override public void keyTyped(KeyEvent e) { // TODO Auto-generated method stub } } private void createAndDisplayGUI(Window window) { frame = new Jframe(); Container container = frame.getContentPane(); container.add(window); window.addKeyListener(new MoveCircle()); frame.setSize(800, 700); frame.setDefaultCloseOperation(Jframe.DISPOSE_ON_CLOSE); frame.setVisible(true); window.requestFocusInWindow(); } public static void main(String[] args) { SwingUtilities.invokeLater(new Runnable() { public void run() { Window window = new Window(); window.createAndDisplayGUI(window); } }); }}
