如何使JButton对按键方法作出反应？

Question

我正在Netbeans中使用JFrame Form制作一个简单的钢琴游戏，我希望能够使用计算机键盘按键来控制JButtons 。 当我想使用ActionPerformed方法并在“设计”选项中keypressed时，它只允许我控制以前用鼠标单击的按钮。 其他按钮不起作用。 我试图通过自己编写keypressed来解决它，但是在这种情况下，当我按键盘键时什么也没发生。

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
    String soundName = "C.wav";
    AudioInputStream audioInputStream = null;
    try {
        audioInputStream = AudioSystem.getAudioInputStream(new
                File(soundName).getAbsoluteFile());
    } catch (UnsupportedAudioFileException | IOException ex) {
        Logger.getLogger(GameWindow.class.getName()).log(Level.SEVERE, null, ex);
    }
    Clip clip = null;
    try {
        clip = AudioSystem.getClip();
    } catch (LineUnavailableException ex) {
        Logger.getLogger(GameWindow.class.getName()).log(Level.SEVERE, null, ex);
    }
    try {
        clip.open(audioInputStream);
    } catch (LineUnavailableException | IOException ex) {
        Logger.getLogger(GameWindow.class.getName()).log(Level.SEVERE, null, ex);
    }
    clip.start();
}
public void keyPressed(KeyEvent evt){
    int keyCode = evt.getKeyCode();
    if (keyCode == KeyEvent.VK_Z) {
        jButton1.getModel().isPressed();
    }
    if (keyCode == KeyEvent.VK_S) {
        jButton2.getModel().isPressed();
    }
}

Answer 1

您可以使用Swing键绑定实现此目的。 请尝试以下示例。 使用InputMap和ActionMap是此示例的重点。

import javax.swing.*;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;

public class ClickButtonsThroughKeyboard
{
  private static Action buttonOneClickAction = new ButtonOneClickAction();
  private static Action buttonTwoClickAction = new ButtonTwoClickAction();

  public static void main(String[] args)
  {
    JButton button1 = new JButton("One");
    button1.addActionListener(buttonOneClickAction);

    button1.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW).put(KeyStroke.getKeyStroke('z'), "z_typed");
    button1.getActionMap().put("z_typed", buttonOneClickAction);

    JButton button2 = new JButton("Two");
    button2.addActionListener(buttonTwoClickAction);

    button2.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW).put(KeyStroke.getKeyStroke('s'), "s_typed");
    button2.getActionMap().put("s_typed", buttonTwoClickAction);

    JFrame f = new JFrame("Click Button Programmatically");
    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    f.getContentPane().setLayout(new FlowLayout());
    f.getContentPane().add(button1);
    f.getContentPane().add(button2);
    f.setBounds(300, 200, 400, 300);
    f.setVisible(true);
  }
}

class ButtonOneClickAction extends AbstractAction
{
  @Override
  public void actionPerformed(ActionEvent e)
  {
    System.out.println("Button One clicked");
  }
}

class ButtonTwoClickAction extends AbstractAction
{
  @Override
  public void actionPerformed(ActionEvent e)
  {
    System.out.println("Button Two clicked");
  }
}