java-全屏窗口无法使用KeyListener或KeyBoardFocusManager获得键盘输入
作者：互联网
我在让KeyBoardFocusManger与全屏窗口一起使用时遇到问题.不管怎样,它都不会得到键盘输入.我使用System.exit(0)和println()来查找对keypressed / released / typed方法的任何调用,但是不会引发任何错误.我已经尝试过KeyListeners；但是当我阅读this之后,我换成了KeyboardFocusManager,同样的事情仍然发生.我真的很绝望.根据我的判断,Window是否无法吸引键盘的注意力？
这是我的主要内容：
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
// Determine if full-screen mode is supported directly
GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
GraphicsDevice gs = ge.getDefaultScreenDevice();
if (gs.isFullScreenSupported()) {
Frame frame = new Frame(gs.getDefaultConfiguration());
SpaceInvaderUI spaceInvaderUI = new SpaceInvaderUI(frame);
// Enter full-screen mode
gs.setFullScreenWindow(spaceInvaderUI);
} else {
JOptionPane.showMessageDialog(null, "Does not support full screen!", "Error 0x01", JOptionPane.ERROR_MESSAGE);
System.exit(1);
}
}
});
}
这是包含KeyBoardFocusManger的UI,并添加到addListeners()方法中：
class SpaceInvaderUI extends Window {
private JPanel drawingPanel;
private Image background;
private JButton btnExit;
public SpaceInvaderUI(Frame frame) {
super(frame);
try {
background = ImageIO.read(getClass().getResourceAsStream("background.png"));
} catch (Exception ex) {
JOptionPane.showMessageDialog(null, "Could not extract resource: " + ex.getMessage(), "Error 0x02", JOptionPane.ERROR_MESSAGE);
System.exit(2);
}
createWindow();
}
private void createComponents() throws HeadlessException {
drawingPanel = new DrawingPanel(background, this);
btnExit = new JButton("Exit");
}
private void createWindow() {
createComponents();
addListeners();
addComponentsToWindow();
}
private void addComponentsToWindow() {
add(drawingPanel, BorderLayout.CENTER);
add(btnExit, BorderLayout.SOUTH);
}
private void addListeners() {
KeyboardFocusManager manager = KeyboardFocusManager.getCurrentKeyboardFocusManager();
manager.addKeyEventDispatcher(new MyDispatcher());
btnExit.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent ae) {
System.exit(0);
}
});
}
private class MyDispatcher implements KeyEventDispatcher {
@Override
public boolean dispatchKeyEvent(KeyEvent e) {
if (e.getID() == KeyEvent.KEY_PRESSED) {
System.out.println("pressed");
System.exit(0);
} else if (e.getID() == KeyEvent.KEY_RELEASED) {
System.out.println("released");
System.exit(0);
} else if (e.getID() == KeyEvent.KEY_TYPED) {
System.out.println("Typed");
System.exit(0);
}
return false;
}
}
}
退出按钮只是因为我厌倦了通过taskmanager杀死我的应用程序.最后,这是我将进行游戏的面板,并且画了我的背景：
public class DrawingPanel extends JPanel {
private final Image background;
private final SpaceInvaderUI invaderUI;
DrawingPanel(Image background, SpaceInvaderUI invaderUI) {
this.background = background;
this.invaderUI = invaderUI;
}
@Override
protected void paintComponent(Graphics grphcs) {
super.paintComponent(grphcs);
grphcs.drawImage(background.getScaledInstance((int) invaderUI.getWidth(), (int) invaderUI.getHeight(), Image.SCALE_SMOOTH), 0, 0, this);
}
}
先感谢您.
编辑：我现在已经尝试在我的drawingPanel上使用键绑定,但是当我按f2时仍然没有任何反应：
class SpaceInvaderUI extends Window {
private JPanel drawingPanel;
private Image background;
private JButton btnExit;
public SpaceInvaderUI(Frame frame) {
super(frame);
try {
background = ImageIO.read(getClass().getResourceAsStream("background.png"));
} catch (Exception ex) {
JOptionPane.showMessageDialog(null, "Could not extract resource: " + ex.getMessage(), "Error 0x02", JOptionPane.ERROR_MESSAGE);
System.exit(2);
}
createWindow();
}
private void createComponents() throws HeadlessException {
drawingPanel = new DrawingPanel(background, this);
btnExit = new JButton("Exit");
}
private void createWindow() {
createComponents();
addListeners();
addComponentsToWindow();
}
private void addComponentsToWindow() {
add(drawingPanel, BorderLayout.CENTER);
add(btnExit, BorderLayout.SOUTH);
}
private void addListeners() {
Action exit = new AbstractAction() {
public void actionPerformed(ActionEvent e) {
System.exit(0);
}
};
drawingPanel.getInputMap().put(KeyStroke.getKeyStroke("F2"),
exit);
btnExit.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent ae) {
System.exit(0);
}
});
}
}
解决方法:
为什么在Swing GUI中使用AWT组件？我担心(但不确定),这样做可能会丢失一些Swing功能.
如果仅捕获选择键和选择键来控制游戏,请考虑使用Key Bindings.
编辑：
不,AWT组件没有问题,但仍然可能不应使用.
编辑2：
由于某些原因,您的顶级窗口未处于聚焦状态.继续测试代码…
编辑3：
使用JFrame对我有用：
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Test3 {
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
GraphicsEnvironment ge = GraphicsEnvironment
.getLocalGraphicsEnvironment();
GraphicsDevice gs = ge.getDefaultScreenDevice();
if (gs.isFullScreenSupported()) {
SpaceInvaderUI spaceInvaderUI = new SpaceInvaderUI(gs.getDefaultConfiguration());
gs.setFullScreenWindow(spaceInvaderUI);
} else {
JOptionPane.showMessageDialog(null,
"Does not support full screen!", "Error 0x01",
JOptionPane.ERROR_MESSAGE);
System.exit(1);
}
}
});
}
}
// class SpaceInvaderUI extends JWindow {
class SpaceInvaderUI extends JFrame {
private JPanel drawingPanel;
private Image background;
private JButton btnExit;
public SpaceInvaderUI(GraphicsConfiguration gc) {
super(gc);
createWindow();
addKeyBindings();
setUndecorated(true);
}
private void addKeyBindings() {
int condition = JPanel.WHEN_IN_FOCUSED_WINDOW;
InputMap inputMap = drawingPanel.getInputMap(condition );
ActionMap actionMap = drawingPanel.getActionMap();
boolean released = false;
KeyStroke upArrowKeyStrokePressed = KeyStroke.getKeyStroke(KeyEvent.VK_UP, 0, released );
String upArrowPressed = "up arrow pressed";
inputMap.put(upArrowKeyStrokePressed , upArrowPressed);
actionMap.put(upArrowPressed, new AbstractAction() {
@Override
public void actionPerformed(ActionEvent arg0) {
System.out.println("up arrow pressed");
}
});
released = true;
String upArrowReleased = "up arrow released";
KeyStroke upArrowKeyStrokeReleased = KeyStroke.getKeyStroke(KeyEvent.VK_UP, 0, released );
inputMap.put(upArrowKeyStrokeReleased , upArrowReleased);
actionMap.put(upArrowReleased , new AbstractAction() {
@Override
public void actionPerformed(ActionEvent arg0) {
System.out.println("up arrow released");
}
});
}
private void createComponents() throws HeadlessException {
drawingPanel = new DrawingPanel(background, this);
btnExit = new JButton("Exit");
}
private void createWindow() {
createComponents();
addListeners();
addComponentsToWindow();
}
private void addComponentsToWindow() {
add(drawingPanel, BorderLayout.CENTER);
add(btnExit, BorderLayout.SOUTH);
}
private void addListeners() {
// KeyboardFocusManager manager = KeyboardFocusManager
// .getCurrentKeyboardFocusManager();
// manager.addKeyEventDispatcher(new MyDispatcher());
btnExit.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent ae) {
System.exit(0);
}
});
}
//
// private class MyDispatcher implements KeyEventDispatcher {
//
// @Override
// public boolean dispatchKeyEvent(KeyEvent e) {
// System.out.println("in dispatch. KeyEvent := " + e);
// if (e.getID() == KeyEvent.KEY_PRESSED) {
// System.out.println("pressed");
// System.exit(0);
// } else if (e.getID() == KeyEvent.KEY_RELEASED) {
// System.out.println("released");
// System.exit(0);
// } else if (e.getID() == KeyEvent.KEY_TYPED) {
// System.out.println("Typed");
// System.exit(0);
// }
// return false;
// }
// }
}
class DrawingPanel extends JPanel {
private final Image background;
private final SpaceInvaderUI invaderUI;
DrawingPanel(Image background, SpaceInvaderUI invaderUI) {
this.background = background;
this.invaderUI = invaderUI;
setBackground(Color.pink);
}
@Override
protected void paintComponent(Graphics grphcs) {
super.paintComponent(grphcs);
}
}
标签：keylistener,java,swing,key-bindings,fullscreen 来源： https://codeday.me/bug/20191010/1887926.html