如何设置Java的默认按钮反应上ENTER键_released_？(How to set the J

在我的应用程序使用一个默认按钮。我想它的时候反应ENTER键被释放。不是当ENTER键被按下。

我删除了KeyStroke从InputMap的按钮。但它没有为我工作。我应该怎么做呢？

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

public class ButtonTest {
    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                buildFrame();
            }
        });
    }

    private static void buildFrame() {
        JFrame f = new JFrame("Test");
        f.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);

        JButton button = new JButton(new AbstractAction("Button") {
            @Override
            public void actionPerformed(ActionEvent e) {
                System.out.println("ButtonTest::actionPerformed: CALLED");
            }
        });

        JButton button2 = new JButton("Button 2");
        InputMap im = button.getInputMap();
        im.put(KeyStroke.getKeyStroke("ENTER"), "none");
        im.put(KeyStroke.getKeyStroke("released ENTER"), "released");

        f.setLayout(new GridBagLayout());
        f.add(button);
        f.add(button2);
        f.getRootPane().setDefaultButton(button);

        f.pack();
        f.setLocationRelativeTo(null);
        f.setVisible(true);
    }
}

这是示例代码。

Answer 1:

JRootPane rootPane = SwingUtilities.getRootPane(/* Your JButton  */); 
rootPane.setDefaultButton(/* Your JButton  */);

Answer 2:

默认按钮键（也就是被触发输入，无论哪个组件focusOwner按钮）在为rootPane的componentInputMap约束，这是它的类型WHEN_IN_FOCUSED_WINDOW的InputMap中。因此从技术上讲，这是对调整的地方：

JComponent content = new JPanel();
content.add(new JTextField("some focusable"));
content.add(new JTextField("something else"));

JXFrame frame = wrapInFrame(content, "default button on released");
Action action = new AbstractAction("do something") {

    @Override
    public void actionPerformed(ActionEvent e) {
        LOG.info("clicked");
    }
};
JButton button = new JButton(action);
content.add(button);
frame.getRootPane().setDefaultButton(button);
// remove the binding for pressed
frame.getRootPane().getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW)
    .put(KeyStroke.getKeyStroke("ENTER"), "none");
// retarget the binding for released
frame.getRootPane().getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW)
    .put(KeyStroke.getKeyStroke("released ENTER"), "press");

请注意：这仍然是从非默认按钮的按下/释放行为不同，因为的rootPane动作只需拨打的button.doClick没有通过武装的行动去/按ButtonModel的间接触发动作。

Answer 3:

    InputMap im = button.getInputMap();
    im.put(KeyStroke.getKeyStroke("ENTER"), "pressed");
    im.put(KeyStroke.getKeyStroke("released ENTER"), "released");

这样做的效果是按钮，执行它的actionPerformed只有一次，当ENTER被释放（如果我理解正确的话，这是你想要的）。

编辑：下面的代码的运行表明的actionPerformed仅在ENTER释放（虽然在视觉上的按钮显示为已经按下了ENTER压）执行

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

public class ButtonTest {
    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                buildFrame();
            }
        });
    }

    private static void buildFrame() {
        JFrame f = new JFrame("Test");
        f.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);

        JButton button = new JButton(new AbstractAction("Button") {
            @Override
            public void actionPerformed(ActionEvent e) {
                System.out.println("ButtonTest::actionPerformed: CALLED");
            }
        });

        InputMap im = button.getInputMap();
        im.put(KeyStroke.getKeyStroke("ENTER"), "pressed");
        im.put(KeyStroke.getKeyStroke("released ENTER"), "released");

        f.add(button);
        f.getRootPane().setDefaultButton(button);

        f.pack();
        f.setLocationRelativeTo(null);
        f.setVisible(true);
    }
}