java - 如何防止在 TextArea 中输入也触发按键绑定(bind)？

Question

我正在尝试在带有拆分 Pane 的 JFrame 中实现热键，其中一个 Pane 上有一个 JTree。键绑定(bind)工作得很好，除了当用户编辑 JTree 节点的名称时，如果他们按下具有键绑定(bind)的键，则在文本区域中键入击键并且它会触发键绑定(bind)。关于如何允许编辑节点，同时仍然实现热键，有什么想法吗？

下面是演示该行为的示例。 “1”和“2”键已绑定(bind)，因此如果您在文本区域中键入其中一个，您将看到弹出窗口。

import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import javax.swing.AbstractAction;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JToolBar;
import javax.swing.KeyStroke;
import javax.swing.SwingUtilities;

public class KeyBindingTest {
    static JButton button1;
    static JButton button2;
    static JPanel panel;

    public KeyBindingTest() {
        panel = new JPanel(new BorderLayout());
        JToolBar tb = new JToolBar();
        tb.setFloatable(false);

        button1 = new JButton("First Button");
        button1.addActionListener(new ButtonAction());
        button2 = new JButton("Second Button");
        button2.addActionListener(new ButtonAction());
        tb.add(button1);
        tb.add(button2);

        panel.add(tb, BorderLayout.PAGE_START);

        JTextArea ta = new JTextArea(10, 30);
        JScrollPane opts = new JScrollPane(ta);
        panel.add(opts, BorderLayout.PAGE_END);

        setKeyBindings(tb);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                KeyBindingTest test = new KeyBindingTest();
                test.createAndShowUI();
            }
        });
    }

    private void setKeyBindings(JToolBar tb) {
        tb.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW).put(KeyStroke.getKeyStroke(KeyEvent.VK_1, 0), "first");
        tb.getActionMap().put("first", new ButtonAction());
        tb.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW).put(KeyStroke.getKeyStroke(KeyEvent.VK_2, 0), "second");
        tb.getActionMap().put("second", new ButtonAction());
    }

    private void createAndShowUI() {
        JFrame frame = new JFrame();
        frame.getRootPane().setDefaultButton(button1);
        frame.setLayout(new BorderLayout());
        frame.add(panel, BorderLayout.CENTER);
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
    }

    public class ButtonAction extends AbstractAction {
        private static final long serialVersionUID = 1L;

        @Override
        public void actionPerformed(ActionEvent e) {
            JOptionPane.showMessageDialog(panel, "You pressed a button \n" + e.paramString());
        }
    }
}

Answer 1

这就是为什么热键通常具有 Alt 或 Control 修饰符的原因。

您可以修改操作来确定哪个组件具有焦点:

@Override
public void actionPerformed(ActionEvent e)
{
    KeyboardFocusManager kfm = KeyboardFocusManager.getCurrentKeyboardFocusManager();
    Component focusedComponent = kfm.getFocusOwner();

    if (focusedComponent instanceof JTextArea)
        return;

    JOptionPane.showMessageDialog(panel, "You pressed a button \n"+e.paramString());
}