我的应用程序具有带菜单栏的主GUI和另一个全屏框架，这使得主GUI的某些部分以全屏独占模式显示。当我处于全屏模式时，我想将菜单栏中的下拉菜单绑定为jpopupmenu。
Swing在JMenu中提供了函数getPopupMenu（）。这个功能乍一看似乎工作正常。我可以将鼠标悬停在菜单项上并移动并查看子菜单。将鼠标悬停在子菜单上会强调子菜单，将鼠标悬停在简单的菜单项（或radiobuttonmenuitem或checkboxmenuitem）上并不强调该项目。但是，我实际上无法点击menuitem。但键盘快捷键实际上工作正常。问题基本上与此论坛上提出的问题相同（但问题仍未解决）：
http://www.java-forums.org/new-java/16463-jmenu-jpopupmenu.html
如果我在初始化并在主GUI中使用/显示菜单栏之后添加JMenuItem（因此当切换到全屏帧时），菜单项实际上是可点击的。此菜单项也可以在主GUI的菜单栏中单击。初始化jMenu后直接执行getPopupMenu（）不会改变任何东西。不使用全屏独占模式也不会改变有关问题的任何内容。
似乎我遗漏了一些重要信息：我正在Mac OSX上测试应用并使用：
System.setProperty("apple.laf.useScreenMenuBar", "true");
使菜单栏使用原生菜单栏。如果我禁用它，弹出菜单按预期工作。这似乎是mac java API中的一个错误？他们有什么方法可以克服，这个？
我为忘记提及这一点而道歉，我不知道这会影响任何事情（虽然看起来很明显）。
答案 0 :(得分：2)
好吧，我可能遗漏了一些东西，但我很快就把它砍成了这个并没有问题
public class PopupFrame extends javax.swing.JFrame {
/**
* Creates new form PopupFrame
*/
public PopupFrame() {
initComponents();
}
/**
* This method is called from within the constructor to initialize the form.
* WARNING: Do NOT modify this code. The content of this method is always
* regenerated by the Form Editor.
*/
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jMenuBar1 = new javax.swing.JMenuBar();
mnuFile = new javax.swing.JMenu();
jMenuItem1 = new javax.swing.JMenuItem();
jMenuItem2 = new javax.swing.JMenuItem();
jMenuItem3 = new javax.swing.JMenuItem();
jMenuItem4 = new javax.swing.JMenuItem();
jMenuItem5 = new javax.swing.JMenuItem();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
addMouseListener(new java.awt.event.MouseAdapter() {
public void mousePressed(java.awt.event.MouseEvent evt) {
doMouseClicked(evt);
}
public void mouseReleased(java.awt.event.MouseEvent evt) {
doMouseClicked(evt);
}
public void mouseClicked(java.awt.event.MouseEvent evt) {
doMouseClicked(evt);
}
});
mnuFile.setText("File");
jMenuItem1.setText("New");
jMenuItem1.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
doActionPerformed(evt);
}
});
mnuFile.add(jMenuItem1);
jMenuItem2.setText("Open");
jMenuItem2.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
doActionPerformed(evt);
}
});
mnuFile.add(jMenuItem2);
jMenuItem3.setText("Save");
jMenuItem3.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
doActionPerformed(evt);
}
});
mnuFile.add(jMenuItem3);
jMenuItem4.setText("Close");
jMenuItem4.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
doActionPerformed(evt);
}
});
mnuFile.add(jMenuItem4);
jMenuItem5.setText("Exit");
jMenuItem5.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
doActionPerformed(evt);
}
});
mnuFile.add(jMenuItem5);
jMenuBar1.add(mnuFile);
setJMenuBar(jMenuBar1);
org.jdesktop.layout.GroupLayout layout = new org.jdesktop.layout.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING)
.add(0, 400, Short.MAX_VALUE)
);
layout.setVerticalGroup(
layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING)
.add(0, 278, Short.MAX_VALUE)
);
pack();
}// </editor-fold>
private void doActionPerformed(java.awt.event.ActionEvent evt) {
JMenuItem mi = (JMenuItem) evt.getSource();
JOptionPane.showMessageDialog(this, "Clicked " + mi.getText());
}
private void doMouseClicked(java.awt.event.MouseEvent evt) {
if (evt.isPopupTrigger()) {
JPopupMenu popupMenu = mnuFile.getPopupMenu();
popupMenu.show(this, evt.getX(), evt.getY());
}
}
/**
* @param args the command line arguments
*/
public static void main(String args[]) {
/*
* Set the Nimbus look and feel
*/
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
/*
* If Nimbus (introduced in Java SE 6) is not available, stay with the
* default look and feel. For details see
* http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException ex) {
java.util.logging.Logger.getLogger(PopupFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(PopupFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(PopupFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(PopupFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
/*
* Create and display the form
*/
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new PopupFrame().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JMenuBar jMenuBar1;
private javax.swing.JMenuItem jMenuItem1;
private javax.swing.JMenuItem jMenuItem2;
private javax.swing.JMenuItem jMenuItem3;
private javax.swing.JMenuItem jMenuItem4;
private javax.swing.JMenuItem jMenuItem5;
private javax.swing.JMenu mnuFile;
// End of variables declaration
}
我道歉，当我3个月大的小睡时，我不得不把它放在一起，所以它快速而丑陋：P
<强>更新
经过一些游戏后，似乎当我们自己调用弹出窗口时，我正在更改弹出窗口的父引用（invoker），这意味着当JMenu尝试显示弹出窗口时，背景都错了。
我将doActionPerformed方法更新为：
JOptionPane.showMessageDialog(this, "Clicked " + mi.getText());
JPopupMenu popupMenu = mnuFile.getPopupMenu();
popupMenu.setInvoker(mnuFile);
基本上，休息弹出窗口的客户端参考。