我想,当我单击“d”按钮时,启动一个计时器。这是为了动画玩家行走。当我按下按键时计时器没有启动,我该怎么办?
我的代码是这样的:
public class Game extends JPanel implements KeyListener {
//Player variables
private BufferedImage playerStanding;
private BufferedImage playerWalking;
private BufferedImage playerFrame;
private boolean walking = false;
private final int PLAYER_HEIGHT = 100;
private final int PLAYER_WIDTH = 100;
private final int INITIAL_X = 0;
private final int INITIAL_Y = 500;
private int x = INITIAL_X;
private int y = INITIAL_Y;
//The timer I want to start on keypress-> "d"
private Timer playerAnimationTimer;
public Game() {
setPreferredSize(new Dimension(800, 800));
setBackground(Color.CYAN);
//Player
try {
playerStanding = ImageIO.read(getClass().getResource("player1.gif"));
playerWalking = ImageIO.read(getClass().getResource("player2.gif"));
playerFrame = playerStanding;
}
catch (IOException ex) {
ex.printStackTrace();
}
playerAnimationTimer = new Timer(500, new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
walking = !walking;
playerFrame = walking ? playerWalking : playerStanding;
x += 10;
if (x > getWidth() - PLAYER_WIDTH) {
x = INITIAL_X;
}
repaint();
}
});
playerAnimationTimer.setRepeats(true);
}
public Dimension setPreferredSize() {
return new Dimension(800, 800);
}
@Override
public void paintComponent(Graphics graphics) {
super.paintComponent(graphics);
Graphics2D graphics2D = (Graphics2D) graphics;
if (playerFrame != null) {
graphics2D.drawImage(playerFrame, x, y, PLAYER_WIDTH, PLAYER_HEIGHT, this);
}
graphics2D.dispose();
}
@Override
public void keyTyped(KeyEvent e) {
//This doesn't work
playerAnimationTimer.start();
}
@Override
public void keyPressed(KeyEvent e) {
}
@Override
public void keyReleased(KeyEvent e) {
}
}
//The class to hold the gamepanel
public class StartGame extends JFrame implements ActionListener {
private static JButton startGame = new JButton();
StartGame() {
setDefaultCloseOperation(WindowConstants.HIDE_ON_CLOSE);
setSize(200, 100);
setVisible(true);
setBackground(Color.BLUE);
setLocationRelativeTo(null);
startGame.setText("Play!");
startGame.setSize(100, 25);
startGame.addActionListener(this);
add(startGame);
}
@Override
public void actionPerformed(ActionEvent e) {
if (e.getSource() == startGame) {
this.setVisible(false);
new GameWindow();
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
new StartGame();
}
});
}
}
如何让计时器在单击“d”按钮时启动?
最佳答案
您的 KeyListener 不起作用,因为您从未将 KeyListener 添加到任何具有焦点的组件中,而焦点是 KeyListener 工作所必需的。
我建议您改用按键绑定(bind)作为一种更干净、更安全的方式来捕获所需的按键。
顺便说一句,永远不要处置从 JVM 提供给您的 Graphics 对象。
为了获得更好的答案,请编辑您的代码以使其符合 mcve标准。您不应该使用任何图像文件,并且它应该不加更改地为我们编译和运行。
关于java - 在按键时启动计时器,java,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/21801180/