正如在类似问题中所讨论的，不要使用KeyListener，而要使用键绑定。摆动计时器可用于重复移动精灵。
编辑
例如：
import java.awt.Color;import java.awt.Dimension;import java.awt.Graphics;import java.awt.event.*;import java.util.EnumMap;import javax.swing.*;@SuppressWarnings("serial")public class Boxxy2 extends JPanel { private static final int PREF_W = 400; private static final int PREF_H = PREF_W; private static final int SQUARE_W = 20; private static final String PRESSED = "pressed"; private static final String RELEASED = "released"; public static final int MOVE_SCALE = 1; private static final int TIMER_DELAY = 5; private int squareX = 0; private int squareY = 0; private int squareW = SQUARE_W; private int squareH = SQUARE_W; private EnumMap<Direction, Boolean> dirMap = new EnumMap<>(Direction.class); public Boxxy2() { setupKeyBinding(); new Timer(TIMER_DELAY, new TimerListener()).start(); } private void setupKeyBinding() { int condition = JComponent.WHEN_IN_FOCUSED_WINDOW; InputMap inMap = getInputMap(condition); ActionMap actMap = getActionMap(); // this uses an enum of Direction that holds ints for the arrow keys for (Direction direction : Direction.values()) { dirMap.put(direction, Boolean.FALSE); int key = direction.getKey(); String name = direction.name(); KeyStroke keyPressed = KeyStroke.getKeyStroke(key, 0, false); KeyStroke keyReleased = KeyStroke.getKeyStroke(key, 0, true); // add the key bindings for arrow key and shift-arrow key inMap.put(keyPressed, name + PRESSED); inMap.put(keyReleased, name + RELEASED); actMap.put(name + PRESSED, new MyKeyAction(this, direction, true)); actMap.put(name + RELEASED, new MyKeyAction(this, direction, false)); } } @Override public Dimension getPreferredSize() { return new Dimension(PREF_W, PREF_H); } @Override protected void paintComponent(Graphics g) { super.paintComponent(g); g.setColor(Color.RED); g.fillRect(squareX, squareY, squareW, squareH); } private static void createAndShowGui() { Boxxy2 mainPanel = new Boxxy2(); Jframe frame = new Jframe("Boxxy2"); frame.setDefaultCloseOperation(Jframe.EXIT_ON_CLOSE); frame.getContentPane().add(mainPanel); frame.pack(); frame.setLocationByPlatform(true); frame.setVisible(true); } public static void main(String[] args) { SwingUtilities.invokeLater(new Runnable() { public void run() { createAndShowGui(); } }); } private class TimerListener implements ActionListener { @Override public void actionPerformed(ActionEvent e) { for (Direction dir : dirMap.keySet()) { if (dirMap.get(dir)) { squareX += MOVE_SCALE * dir.getRight(); squareY += MOVE_SCALE * dir.getDown(); } } repaint(); } } public void setMovement(Direction direction, boolean keyPressed) { dirMap.put(direction, keyPressed); }}enum Direction { UP(KeyEvent.VK_UP, 0, -1), DOWN(KeyEvent.VK_DOWN, 0, 1), LEFt(KeyEvent.VK_LEFT, -1, 0), RIGHt(KeyEvent.VK_RIGHT, 1, 0); private int key; private int right; private int down; private Direction(int key, int right, int down) { this.key = key; this.right = right; this.down = down; } public int getKey() { return key; } public int getRight() { return right; } public int getDown() { return down; }}// Actions for the key binding@SuppressWarnings("serial")class MyKeyAction extends AbstractAction { private Boxxy2 boxxy2; private Direction direction; private boolean keyPressed; public MyKeyAction(Boxxy2 boxxy2, Direction direction, boolean keyPressed) { this.boxxy2 = boxxy2; this.direction = direction; this.keyPressed = keyPressed; } @Override public void actionPerformed(ActionEvent e) { boxxy2.setMovement(direction, keyPressed); }}
