我正在java中製作一個非常簡單的pong遊戲，我正在使用KeyListener進行此操作。我想要它，所以當用戶按下鍵盤上的右鍵或者左鍵時，乒乓塊就會朝這個方向行進。這是一個足夠簡單的任務，但我發現當用戶按住鍵時，塊會移動一次，短時間停止，然後繼續移動，直到用戶釋放鍵。我注意到這種情況發生在您試圖按住計算機上的字母鍵時。如果我嘗試按住「A」鍵，計算機會做什麼：Java KeyListener口吃
一個[暫停] aaaaaaaaaaaaaaaa
有什麼方法來禁用這個口吃，因爲它是在的方式獲得我的小遊戲流暢的遊戲。快速解決將深受讚賞。
爲例子...
更新爲simp例如
在大多數遊戲中，您應該對「狀態更改」做出反應，而不是實際的關鍵事件。這意味着，實際上改變的狀態可以是可變的事件（想自定義鍵）
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import javax.swing.AbstractAction;
import javax.swing.ActionMap;
import javax.swing.InputMap;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.KeyStroke;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class SinglePressKeyBinding {
public static void main(String[] args) {
new SinglePressKeyBinding();
}
public SinglePressKeyBinding() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
private JLabel message;
private boolean spacedOut = false;
public TestPane() {
message = new JLabel("Waiting");
setLayout(new GridBagLayout());
add(message);
InputMap im = getInputMap(WHEN_IN_FOCUSED_WINDOW);
ActionMap am = getActionMap();
im.put(KeyStroke.getKeyStroke(KeyEvent.VK_SPACE, 0, false), "space-pressed");
im.put(KeyStroke.getKeyStroke(KeyEvent.VK_SPACE, 0, true), "space-released");
am.put("space-pressed", new AbstractAction() {
@Override
public void actionPerformed(ActionEvent e) {
if (spacedOut) {
message.setText("I'm ignoring you");
} else {
spacedOut = true;
message.setText("Spaced out");
}
}
});
am.put("space-released", new AbstractAction() {
@Override
public void actionPerformed(ActionEvent e) {
spacedOut = false;
message.setText("Back to earth");
}
});
}
@Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
}
}
我本來約按鍵綁定一個答案，但一個小的測試後，我發現，他們仍然有同樣的口吃問題。
不要依賴OS的重複率。它對於每個平臺都可能不同，用戶也可以對其進行定製。
而是使用計時器來安排事件。您在keyPressed上啓動Timer並在keyReleased上停止Timer。
import java.awt.*;
import java.awt.event.*;
import java.net.*;
import java.util.Map;
import java.util.HashMap;
import javax.imageio.ImageIO;
import javax.swing.*;
public class KeyboardAnimation implements ActionListener
{
private final static String PRESSED = "pressed ";
private final static String RELEASED = "released ";
private final static Point RELEASED_POINT = new Point(0, 0);
private JComponent component;
private Timer timer;
private Map<String, Point> pressedKeys = new HashMap<String, Point>();
public KeyboardAnimation(JComponent component, int delay)
{
this.component = component;
timer = new Timer(delay, this);
timer.setInitialDelay(0);
}
public void addAction(String keyStroke, int deltaX, int deltaY)
{
// InputMap inputMap = component.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW);
InputMap inputMap = component.getInputMap();
ActionMap actionMap = component.getActionMap();
String pressedKey = PRESSED + keyStroke;
KeyStroke pressedKeyStroke = KeyStroke.getKeyStroke(pressedKey);
Action pressedAction = new AnimationAction(keyStroke, new Point(deltaX, deltaY));
inputMap.put(pressedKeyStroke, pressedKey);
actionMap.put(pressedKey, pressedAction);
String releasedKey = RELEASED + keyStroke;
KeyStroke releasedKeyStroke = KeyStroke.getKeyStroke(releasedKey);
Action releasedAction = new AnimationAction(keyStroke, RELEASED_POINT);
inputMap.put(releasedKeyStroke, releasedKey);
actionMap.put(releasedKey, releasedAction);
}
private void handleKeyEvent(String keyStroke, Point moveDelta)
{
// Keep track of which keys are pressed
if (RELEASED_POINT == moveDelta)
pressedKeys.remove(keyStroke);
else
pressedKeys.put(keyStroke, moveDelta);
// Start the Timer when the first key is pressed
if (pressedKeys.size() == 1)
{
timer.start();
}
// Stop the Timer when all keys have been released
if (pressedKeys.size() == 0)
{
timer.stop();
}
}
// Invoked when the Timer fires
public void actionPerformed(ActionEvent e)
{
moveComponent();
}
// Move the component to its new location
private void moveComponent()
{
int componentWidth = component.getSize().width;
int componentHeight = component.getSize().height;
Dimension parentSize = component.getParent().getSize();
int parentWidth = parentSize.width;
int parentHeight = parentSize.height;
// Calculate new move
int deltaX = 0;
int deltaY = 0;
for (Point delta : pressedKeys.values())
{
deltaX += delta.x;
deltaY += delta.y;
}
// Determine next X position
int nextX = Math.max(component.getLocation().x + deltaX, 0);
if (nextX + componentWidth > parentWidth)
{
nextX = parentWidth - componentWidth;
}
// Determine next Y position
int nextY = Math.max(component.getLocation().y + deltaY, 0);
if (nextY + componentHeight > parentHeight)
{
nextY = parentHeight - componentHeight;
}
// Move the component
component.setLocation(nextX, nextY);
}
private class AnimationAction extends AbstractAction implements ActionListener
{
private Point moveDelta;
public AnimationAction(String keyStroke, Point moveDelta)
{
super(PRESSED + keyStroke);
putValue(ACTION_COMMAND_KEY, keyStroke);
this.moveDelta = moveDelta;
}
public void actionPerformed(ActionEvent e)
{
handleKeyEvent((String)getValue(ACTION_COMMAND_KEY), moveDelta);
}
}
public static void main(String[] args)
{
JPanel contentPane = new JPanel();
contentPane.setLayout(null);
Icon dukeIcon = null;
try
{
dukeIcon = new ImageIcon("dukewavered.gif");
// dukeIcon = new ImageIcon(ImageIO.read(new URL("http://duke.kenai.com/iconSized/duke4.gif")));
}
catch(Exception e)
{
System.out.println(e);
}
JLabel duke = new JLabel(dukeIcon);
duke.setSize(duke.getPreferredSize());
duke.setLocation(100, 100);
contentPane.add(duke);
KeyboardAnimation navigation = new KeyboardAnimation(duke, 24);
navigation.addAction("LEFT", -3, 0);
navigation.addAction("RIGHT", 3, 0);
navigation.addAction("UP", 0, -3);
navigation.addAction("DOWN", 0, 3);
navigation.addAction("A", -5, 0);
navigation.addAction("S", 5, 0);
navigation.addAction("Z", 0, -5);
navigation.addAction("X", 0, 5);
navigation.addAction("V", 5, 5);
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
// frame.getContentPane().add(new JTextField(), BorderLayout.SOUTH);
frame.getContentPane().add(contentPane);
frame.setSize(600, 600);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}
此代碼在Windows上進行了測試，其中事件的順序是keyPressed，keyPressed，keyPressed ... keyReleased。然而，我認爲在Mac（或Unix）上，事件的順序是keyPressed，keyReleased，keyPressed，keyReleased ...所以我不確定這段代碼是否會比當前代碼更好地工作。
只是FYI，這個引用來自我，但我不是OP。 – syb0rg 2013-05-03 20:53:05
一個好主意是爲你想要跟蹤的鍵設置布爾值，然後在按鍵事件中激活其中一個布爾值，然後在釋放的鍵上停用它。它將消除按鍵的滯後，並允許多個按鍵！
我最初有一個關於鍵綁定的答案，但經過一些測試後，我發現他們仍然有相同的口吃問題。然而，對於其他的東西+1。 – syb0rg 2013-05-02 01:47:42
@ syb0rg這就是爲什麼你需要那個小旗子;）。最後一個例子展示了允許按鍵事件應用加速度增量的簡潔想法，按下時間越長，增量增加的越多，直到它被釋放並且增量反轉，隨着時間推移減慢對象;） – MadProgrammer 2013-05-02 01:51:55
@ syb0rg添加了一個簡單的例子來演示原理;） – MadProgrammer 2013-05-02 01:58:57