Java 向使用ActionListener的JButton添加keylistener或键绑定

Java 向使用ActionListener的JButton添加keylistener或键绑定,java,swing,jbutton,keylistener,Java,Swing,Jbutton,Keylistener,在下一个示例中,我需要一些关于向按钮添加keylistener或键绑定的帮助。我想当我按下键盘上的A或B时,做出和用鼠标按下一样的动作 import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JPanel;

在下一个示例中,我需要一些关于向按钮添加keylistener或键绑定的帮助。我想当我按下键盘上的A或B时,做出和用鼠标按下一样的动作

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;

public class NetTest {

    static JButton btnA = new JButton("A");
    static JButton btnB = new JButton("B");
    static JPanel jp = new JPanel();
    static JFrame jf = new JFrame("Test APP");
    static JLabel jl = new JLabel("Which button was clicked ?");

    static ActionListener action = new ActionListener() {
        public void actionPerformed(ActionEvent e) {
            jl.setText(((JButton)e.getSource()).getText());
        }
    };

    public static void main(String[] args) {
        jf.setVisible(true);
        jf.setSize(400, 400);
        jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        jp.add(btnA);
        jp.add(btnB);
        jp.add(jl);
        jf.add(jp);

        btnA.addActionListener(action);
        btnB.addActionListener(action);
    }
}

为了收听
KeyEvents
,您需要使用和方法来放置要收听的输入事件和相应的操作。试试这个例子:

import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import javax.swing.AbstractAction;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;

public class Demo{

    private void initGUI(){
        AbstractAction buttonPressed = new AbstractAction() {
            @Override
            public void actionPerformed(ActionEvent e) {
                System.out.println(e.getActionCommand());
            }
        };

        JButton submit = new JButton("Submit");
        submit.addActionListener(buttonPressed);

        /*
         * Get the InputMap related to JComponent.WHEN_IN_FOCUSED_WINDOW condition
         * to put an event when A key is pressed
         */
        submit.getInputMap(javax.swing.JComponent.WHEN_IN_FOCUSED_WINDOW).
                put(javax.swing.KeyStroke.getKeyStroke(java.awt.event.KeyEvent.VK_A,0), "A_pressed");
        /*
         * Add an action when the event key is "A_pressed"
         */
        submit.getActionMap().put("A_pressed", buttonPressed);

        /*
         * Same as above when you press B key
         */
        submit.getInputMap(javax.swing.JComponent.WHEN_IN_FOCUSED_WINDOW).
                put(javax.swing.KeyStroke.getKeyStroke(java.awt.event.KeyEvent.VK_B,0), "B_pressed");
        submit.getActionMap().put("B_pressed", buttonPressed);

        JPanel content = new JPanel(new FlowLayout());
        content.add(new JLabel("Test:"));
        content.add(submit);

        JFrame frame = new JFrame("Demo");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setContentPane(content);
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                new Demo().initGUI();
            }
        });

    }
}
注意:当按下
JButton
或A/B键时,此示例使用相同的
AbstractAction
,但输出将取决于谁是事件源


注2:如果您使用
JComponent.WHEN_IN_FOCUSED_WINDOW
条件,则只要按A或B键,您的操作就会执行。当您有文本输入组件,如
JTextfield
JTextArea
且最终用户几乎肯定会多次按A或B键时,不需要此行为。如果是这种情况,那么您将不得不使用
JComponent.WHEN\u FOCUSED\u组件的祖先\u
条件

如果我理解您想要实现的目标,那么基本上您需要监听两个特定的键盘事件(按下“A”键或“B”键),并切换标签,就像您单击两个按钮之一一样

您只需向框架中添加一个KeyListener,并实现其回调以仅响应键入的“a”或“B”。 还记得在JFrame对象上调用setFocusable(false)

    jf.setFocusable(true);
    jf.addKeyListener( new KeyListener() {

        @Override
        public void keyTyped( KeyEvent evt ) {
        }

        @Override
        public void keyPressed( KeyEvent evt ) {
        }

        @Override
        public void keyReleased( KeyEvent evt ) {
        }
    } );

dic19我按照您对保存按钮所说的那样完成了我的功能。这是我的代码。但它对我不起作用。我在这里添加了我的代码。请检查并帮助我。AbstractAction buttonPressed=new AbstractAction(){@Override public void actionPerformed(ActionEvent e2){System.out.println(e2.getActionCommand());};buttonSave.addActionListener(buttonPressed);buttonSave.getInputMap(javax.swing.JComponent.WHEN_在聚焦窗口中)。put(javax.swing.KeyStroke.getKeyStroke(java.awt.event.KeyEvent.VK_S,0),“保存”);buttonSave.getActionMap().put(“保存”,buttonPressed);