带KeyAdapter的java键盘输入
我想用java做一个简单的游戏,你可以在4个方向移动玩家(防守队员)。我尝试使用密钥适配器进行密钥检测,但没有成功。可能是什么问题(我尝试在按键时执行System.out.println以确保问题不在Defender上)? 代码:
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
public class DefenderComponent extends JPanel implements ActionListener {
private static final long serialVersionUID = 1L;
private static final int WIDTH = 160;
private static final int HEIGHT = 120;
private static final int SCALE = 4;
Defender player = new Defender();
public DefenderComponent() {
Dimension size = new Dimension(WIDTH * SCALE, HEIGHT * SCALE);
setMinimumSize(size);
setMaximumSize(size);
setPreferredSize(size);
addKeyListener(new TKeyListener());
Timer timer = new Timer(5, this);
timer.start();
}
public static void main(String[] args) {
JFrame frame = new JFrame("Test2");
frame.add(new DefenderComponent());
frame.pack();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setResizable(false);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
frame.setFocusable(true);
new DefenderComponent();
}
public void paintComponent(Graphics g){
Graphics2D g2d = (Graphics2D) g;
Image i = player.getImage();
g2d.drawImage(i, player.getX(), player.getY(), i.getWidth(this) * SCALE, i.getHeight(this) * SCALE, this);
}
public void actionPerformed(ActionEvent e) {
player.move();
repaint();
}
}
# 1 楼答案
KeyEvents仅为具有焦点的组件生成。默认情况下,JPanel不可聚焦
不要使用KeyListener。相反,您应该使用更灵活的键绑定
有关更多信息和示例,请参见Motion Using the Keyboard
# 2 楼答案
这就是你错过的
那句话说。这个类是一个ActionListener。当你收到一个动作时,请呼叫这个类
如果要将ActionListener添加到JPanel