Question

我需要使用自定义组件显示swing弹出窗口。弹出窗口应保持可见，直到我自己隐藏它，但不应该得到焦点。

我有一些其他开发人员编写的代码，它按以下方式执行：

       popupMenu = new JPopupMenu();
       popupMenu.add(myCustomComponent, BorderLayout.CENTER);
       popupMenu.setFocusable(false);
       popupMenu.setVisible(true);
       popupMenu.show(parentComponent, x, y);

这似乎有效，但有一个错误 - 当弹出窗口可见时，弹出窗口会消耗组件外部的第一次鼠标点击。所以我需要点击两次将焦点设置到另一个组件。

我该如何解决？或者制作弹出窗口的正确方法是什么？

更新

最后我设法用短代码片段重现了我的问题。感谢Guillaume Polet为我提供了一个起点。

以下是代码：

import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;

import javax.swing.*;

public class TestJPopup {

    protected void initUI() {
        JFrame frame = new JFrame(TestJPopup.class.getSimpleName());
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        final JTextField textField = new JTextField("Some text field");
        frame.add(textField, BorderLayout.WEST);
        final JButton buttonToHit = new JButton("Hit me");
        buttonToHit.addActionListener(new ActionListener() {

            public void actionPerformed(ActionEvent e) {
                JOptionPane.showMessageDialog(buttonToHit, "You hit the button successfully");
            }
        });
        frame.add(buttonToHit);
        frame.setSize(200, 100);
        frame.setVisible(true);

        final JPopupMenu popup = new JPopupMenu();
        popup.add(new JLabel("<html>Hey!<br>I'm the popup window!</html>"),
                BorderLayout.NORTH);
        popup.setFocusable(false);
        popup.setVisible(true);
        popup.show(textField, 60, 60);

        // I want to activate popup when user clicks in the text field
        textField.addMouseListener(new MouseAdapter() {
            @Override
            public void mouseClicked(MouseEvent e) {
                if (popup != null) {
                    popup.show(textField, 60, 60);
                }
            }
        });
    }

    public static void main(String[] args) throws Exception {
        Class lnfClass = Class.forName("com.sun.java.swing.plaf.windows.WindowsLookAndFeel", true,
                Thread.currentThread().getContextClassLoader());
        LookAndFeel feel = (LookAndFeel) lnfClass.newInstance();
        UIManager.setLookAndFeel(feel);

        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                new TestJPopup().initUI();
            }
        });
    }
}

两个关键时刻：

使用Windows外观（默认不可重现）
鼠标侦听器附加到主框架中的文本字段

Answer 1

不是答案，而只是一个示例SSCCE，我目前无法重现您描述的行为。也许从这段代码开始，尝试重现错误并使用修改后的非工作代码编辑帖子。

import java.awt.BorderLayout;
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.JOptionPane;
import javax.swing.JPopupMenu;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;

public class TestJPopup {

    protected void initUI() {
        JFrame frame = new JFrame(TestJPopup.class.getSimpleName());
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        JLabel leftLabel = new JLabel("Left");
        frame.add(leftLabel, BorderLayout.WEST);
        final JButton buttonToHit = new JButton("Hit me");
        buttonToHit.addActionListener(new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent e) {
                JOptionPane.showMessageDialog(buttonToHit, "You hit the button successfully");
            }
        });
        frame.add(buttonToHit);
        frame.setSize(500, 400);
        frame.setVisible(true);
        JPopupMenu popupMenu = new JPopupMenu();
        popupMenu.add(new JLabel("<html>A Custom<br>component<br>made to<br> simulate <br>your custom component</html>"),
                BorderLayout.NORTH);
        JTextField textfield = new JTextField(30);
        popupMenu.add(textfield);
        popupMenu.setFocusable(false);
        popupMenu.setVisible(true);
        popupMenu.show(leftLabel, 20, 20);
        // Let's force the focus to be in a component in the popupMenu
        textfield.requestFocusInWindow();
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                new TestJPopup().initUI();
            }
        });
    }
}

Answer 2

不是解决方案，但是：

对我来说看起来像个错误，即使是普通的componentPopup也表现出同样的错误行为（在winLAF和Nimbus中，而不是在Metal中）：

JTextField field = new JTextField("some popup owner");
JPopupMenu menu = new JPopupMenu();
menu.add("dummy");
field.setComponentPopupMenu(menu);
Action action = new AbstractAction("hit me!") {

    @Override
    public void actionPerformed(ActionEvent e) {
        LOG.info("got hit!");
    }
};
JComponent content = new JPanel();
content.add(new JButton(action));
content.add(field);

Answer 3

快速研究和/或为未来的读者，

此问题可以重现并呈现，

a）JPopup

b）JMenu
在jdk1.6.0_25和jdk1.7.0_04，
WinXp和Win7上的同一问题，
Look and Feel至SystemLookAndFeel / WindowsLookAndFeel，

Answer 4

以下是评论中 mKorbel 提出的JWindow而不是JPopupMenu的可能解决方法：

import java.awt.*;
import java.awt.event.*;

import javax.swing.*;

public class TestJPopup {

    protected void initUI() {
        final JFrame frame = new JFrame(TestJPopup.class.getSimpleName());
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        final JTextField textField = new JTextField("Some text field");
        frame.add(textField, BorderLayout.WEST);
        final JButton buttonToHit = new JButton("Hit me");
        buttonToHit.addActionListener(new ActionListener() {

            public void actionPerformed(ActionEvent e) {
                JOptionPane.showMessageDialog(buttonToHit, "You hit the button successfully");
            }
        });
        frame.add(buttonToHit);
        frame.setSize(200, 70);
        frame.setVisible(true);

        final JWindow popup = new JWindow();
        popup.getContentPane().add(new JLabel("<html>Hey!<br>I'm the popup window!</html>"),
                BorderLayout.NORTH);
        popup.setLocation(frame.getLocation().x + 60, frame.getLocation().y + 60);
        popup.pack();
        popup.setFocusable(false);
        popup.setVisible(true);

        // I want to activate popup when user clicks in the text field
        textField.addMouseListener(new MouseAdapter() {
            @Override
            public void mouseReleased(MouseEvent e) {
                if (popup != null) {
                    popup.setVisible(true);
                    popup.setLocation(frame.getLocation().x + 60, frame.getLocation().y + 60);
                    popup.toFront();
                }
            }
        });

        textField.addFocusListener(new FocusAdapter() {
            @Override
            public void focusLost(FocusEvent e) {
                if (popup != null) {
                    popup.setVisible(false);
                }
            }
        });
    }

    public static void main(String[] args) throws Exception {
        Class lnfClass = Class.forName("com.sun.java.swing.plaf.windows.WindowsLookAndFeel", true,
                Thread.currentThread().getContextClassLoader());
        LookAndFeel feel = (LookAndFeel) lnfClass.newInstance();
        UIManager.setLookAndFeel(feel);

        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                new TestJPopup().initUI();
            }
        });
    }
}

Answer 5

以下是解决问题的神奇之处：

UIManager.put("PopupMenu.consumeEventOnClose", Boolean.FALSE);

在查看BasicPopupMenuUI类的源代码后，我发现了这一点。显然，根据代码中的以下注释，这种行为是一种深思熟虑的设计选择，但它对我来说确实感觉像是一个错误。

        // Ask UIManager about should we consume event that closes
        // popup. This made to match native apps behaviour.

顺便说一句，它也发生在Java 5和6中。

Swing持久弹出窗口

5 个答案: