Develop Reference

How to hide a JPopupMenu by pressing a button?

I'm making a program that has a popup menu with two buttons, one of which should close the popup menu, but I have no idea how to do that and googling hasn't gone too well.
I've tried using popup.hide() but then the menu wouldn't come back, despite doing so when I tried just moving the popup. It also required me to put a SuppressWarning in that case and it took a few seconds for it to close at all. Is there any better way of doing it?
I'm not sure what kind of code is relevant, but here's the relevant buttons and their roles in this(I skipped all the creating the GUI parts that didn't seem relevant, everything looks good and I know that the buttons are working):
package test;
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
interface CustomButton {
JButton create();
void react(JPopupMenu popup, JFrame frame);
}
class ErrandsButton implements CustomButton {
private JButton errands = new JButton("Errands");
public JButton create() {
return errands;
}
public void react(JPopupMenu popup, JFrame frame) {
errands.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
popup.show(frame, 120, 65);
}
});
}
}
class Test {
static JFrame frame = new JFrame("List");
static CustomButton errands = new ErrandsButton();
static JButton cancelTask = new JButton("Cancel");
static JPopupMenu popup = new JPopupMenu();
static void cancelTask() {
cancelTask.addActionListener(new ActionListener() {
#SuppressWarnings("deprecation")
public void actionPerformed(ActionEvent e) {
popup.hide();
}
});
}
public static void main(String args[]) {
createInterface();
cancelTask();
errands.react(popup, frame);
}
static void createInterface() {
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(500, 500);
JPanel popup1 = new JPanel();
JPanel button = new JPanel();
popup1.add(cancelTask);
popup.add(popup1);
frame.add(popup);
button.add(errands.create());
frame.getContentPane().add(BorderLayout.CENTER, button);
frame.setVisible(true);
}
}

Use popup.setVisible(true) and popup.setVisible(false).

frame.add(popup); is the problem. Do not add a JPopupMenu to a Container. Instead, use setComponentPopupMenu.
Alternatively, you could do the work yourself by adding a MouseListener whose mousePressed, mouseReleased and mouseClicked methods call isPopupTrigger and show. (It is vital that you do this in all three of those methods—different platforms have different conditions for showing popup menus.)
But really, using setComponentPopupMenu is easier.

JMenuItem shortcuts Ctrl-C / Ctrl-V or Ctrl-Insert / Shift-Insert don't work anymore

I have an older stand alone java swing-based app that uses JFrame with JMenuBar containing multiple Jmenu elements (with respective JMenuItem items).
After upgrading to the latest 1.6.0_41 (or 1.7.x) JVM on Windows (7 and vista) I've noticed that the menu item with the shortcut Ctrl-C (or Ctrl-Insert) doesn't receive its ActionEvent anymore if JTable is added to the frame. The menu ActionListener is invoked if the menu is accessed by the mouse click however. The shortcut works if JTable is removed. If I change the shortcut combination to something other than Ctrl-C or Ctrl-Insert (i.e. Ctrl-L) the ActionListener is invoked.
The way it used to work (I've just confirmed it with jvm 1.4, on Windows Vista - I know it's been awhile since that environment got any serious attention :) is that Ctrl-C will perform the standard copy to clipboard function inside of the JTable if the focus was inside of an editable field. Otherwise my menu ActionListener was invoked via shortcut assigned through setAccelerator() method.
It looks like JTable implementation changed in 1.6.* to process Ctrl-C bound event differently on Windows.
Running this app on Mac OS (JVM 1.6.0_43) I can see ActionListener is invoked via Ctrl-C shortcut. Although it might be because the JTable uses Command-C instead of Ctrl-C to copy to the clipboard under Mac OS.
I've extracted the relevant portion of the code that demonstrates the problem. Any suggestions are greatly appreciated.
public class TestFrame extends JFrame {
public TestFrame(String title) {
super(title);
}
private void init() {
getContentPane().setLayout(new BorderLayout());
addMenu();
addTable();
// Change default exit operation
setDefaultCloseOperation(EXIT_ON_CLOSE);
pack();
setVisible(true);
}
private void addTable() {
JTable jTable = new JTable(createTableModel());
// Place table in JScrollPane
JScrollPane scrollPane = new JScrollPane(jTable);
// Add Table
add(scrollPane, BorderLayout.CENTER);
}
private TableModel createTableModel() {
Object[][] data = new Object[][]{
{new Date(), "First Row, 2nd column", "First Row, 3rd column"},
{new Date(), "Second Row, 2nd column", "Second Row, 3rd column"},
};
Object[] columnNames = new Object[]{"Date", "Type", "Description"};
DefaultTableModel model = new DefaultTableModel(data, columnNames) {
public boolean isCellEditable(int row, int column) {
return column != 0;
}
};
return model;
}
private void addMenu() {
// Create the menu bar.
JMenuBar menuBar = new JMenuBar();
setJMenuBar(menuBar);
JMenu editMenu = new JMenu("Edit");
menuBar.add(editMenu);
TestActionListener listener = new TestActionListener();
JMenuItem menuItem = null;
menuItem = new JMenuItem("Copy 1");
menuItem.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_INSERT, ActionEvent.CTRL_MASK));
menuItem.addActionListener(listener);
editMenu.add(menuItem);
menuItem = new JMenuItem("Copy 2");
menuItem.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_C, ActionEvent.CTRL_MASK));
menuItem.addActionListener(listener);
editMenu.add(menuItem);
menuItem = new JMenuItem("Copy 3");
menuItem.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_L, ActionEvent.CTRL_MASK));
menuItem.addActionListener(listener);
editMenu.add(menuItem);
}
public static void main(String[] args) {
TestFrame frame = new TestFrame("Test");
frame.init();
}
private static class TestActionListener implements ActionListener {
public void actionPerformed(ActionEvent e) {
System.out.println("TestFrame.TestActionListener.actionPerformed(): e="+ e);
}
}
}

The problem is that your frame is not focused and there are no elements in your whole component hierarchy which has the focus, meaning that no one will "grab" the event and try to do something with it. Since JMenuItem's bind their shortcut to the input map JComponent.WHEN_IN_FOCUSED_WINDOW, your shortcut never "answers" the event.
To fix this, either put the focus on one of the component or directly on the JFrame (for example with frame.requestFocusInWindow();). Small example here:
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.KeyStroke;
import javax.swing.SwingUtilities;
public class TestFrame extends JFrame {
public TestFrame(String title) {
super(title);
}
private void init() {
getContentPane().setLayout(new BorderLayout());
addMenu();
addTable();
// Change default exit operation
setDefaultCloseOperation(EXIT_ON_CLOSE);
pack();
setVisible(true);
}
private void addTable() {
JTable jTable = new JTable();
// Place table in JScrollPane
JScrollPane scrollPane = new JScrollPane(jTable);
// Add Table
add(scrollPane, BorderLayout.CENTER);
}
private void addMenu() {
// Create the menu bar.
JMenuBar menuBar = new JMenuBar();
setJMenuBar(menuBar);
JMenu editMenu = new JMenu("Edit");
menuBar.add(editMenu);
TestActionListener listener = new TestActionListener();
JMenuItem menuItem = null;
menuItem = new JMenuItem("Copy 1");
menuItem.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_INSERT, KeyEvent.CTRL_MASK));
menuItem.addActionListener(listener);
editMenu.add(menuItem);
menuItem = new JMenuItem("Copy 2");
menuItem.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_C, KeyEvent.CTRL_MASK));
menuItem.addActionListener(listener);
editMenu.add(menuItem);
menuItem = new JMenuItem("Copy 3");
menuItem.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_L, KeyEvent.CTRL_MASK));
menuItem.addActionListener(listener);
editMenu.add(menuItem);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
TestFrame frame = new TestFrame("Test");
frame.init();
frame.requestFocusInWindow();
}
});
}
private static class TestActionListener implements ActionListener {
#Override
public void actionPerformed(ActionEvent e) {
System.out.println("TestFrame.TestActionListener.actionPerformed(): e=" + e);
}
}
}
Additional remarks:
Don't extend JFrame if not needed
Start your UI from the Event Dispatching Thread (EDT) by using SwingUtilities.invokeLater()

If you question is how to remove the Control+C binding from the table then you can do:
KeyStroke copy = KeyStroke.getKeyStroke("control C");
InputMap im = table.getInputMap(JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT);
im.getParent().remove(copy);
However, this will remove the binding from all tables.

JPopupMenu closes when child popup opens

I have a JComboBox (among other components) inside a JPopupMenu. It turns out that whenever I open the combo box's popup (to select an item), the parent JPopupMenu closes. I've been trying to find a way to override this feature, to no avail.
Does anyone have any suggestions to prevent closing the parent JPopupMenu? Thanks!

that not possible directly, its very hard to override known bug, in other hands Swing doesn't allows two lightwieght popup components in same time
import javax.swing.*;
import java.awt.event.*;
public class Test {
public static void main(String[] args) {
JFrame frame = new JFrame();
frame.setSize(400, 400);
frame.setVisible(true);
String[] list = {"1", "2", "3", "4",};
JComboBox comb = new JComboBox(list);
final JPopupMenu pop = new JPopupMenu();
pop.add(comb);
frame.addMouseListener(new MouseAdapter() {
#Override
public void mousePressed(MouseEvent e) {
System.out.println("mousePressed");
pop.show(e.getComponent(), e.getX(), e.getY());
}
});
}
}
but workaround is very simple use JWindows or un-decorated JDialog with JComboBox instead of JPopup

JPopupPanel closed when click on its JPopupMenu

I have a JPopupPanel showing up when a button is clicked.
This JPopupPanel has a JPopupMenu which shows up with the mouse right click, showing different options.
When left button pressed to choose one of this options in the PopupMenu, the PopupPanel closes leaving the PopupMenu by itself for a moment, and when the button is released, the PopupMenu also dissapears (as expected), but the action cannot be seen in the PopupPanel since it is already closed.
How can I avoid the JPopupPanel to close when choosing one of the options of the JPopupMenu?
Thanks

Sorry I do not have experience using JPopupPanel. Thus, I can only offer a simple hack.
I would suspect that you can do something similar as in my example (below) where I 'ignore' hiding popup menu on an option select.
My approach here is to reshow the popup menu on an option selection. So fallowing this maybe you can try and reshow your panel when it hides.
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Point;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import javax.swing.JFrame;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JPopupMenu;
import javax.swing.SwingUtilities;
public class JPopupMenuIgnoreOptionCloseOnClick extends JPanel
{
private static final long serialVersionUID = 1L;
private JPopupMenu popup = new JPopupMenu("Oi I am popup");
private MouseListener mL = new MouseAdapter()
{
#Override
public void mousePressed(MouseEvent e)
{
System.out.println("mL mousePressed e.isP="+e.isPopupTrigger());
super.mousePressed(e);
showPopup(e);
}
#Override
public void mouseReleased(MouseEvent e)
{
System.out.println("mL mouseReleased e.isP="+e.isPopupTrigger());
super.mouseReleased(e);
showPopup(e);
}
private void showPopup(MouseEvent e)
{
if(e.isPopupTrigger())
{
prevLocation = e.getPoint();
popup.show(e.getComponent(), e.getX(), e.getY());
}
}
};
private Point prevLocation = null;
private MouseListener optionML = new MouseAdapter()
{
#Override
public void mouseReleased(MouseEvent e)
{
System.out.println("optionML mouseReleased prevLocation="+prevLocation);
e.consume();
popup.show(JPopupMenuIgnoreOptionCloseOnClick.this, prevLocation.x,prevLocation.y);
}
};
public JPopupMenuIgnoreOptionCloseOnClick()
{
addMouseListener(mL);
JMenuItem opt1 =new JMenuItem("Option 1");
opt1.addMouseListener(optionML);
popup.add(opt1);
JMenuItem opt2 =new JMenuItem("Option 2");
opt2.addMouseListener(optionML);
popup.add(opt2);
JMenuItem opt3 =new JMenuItem("Option 3");
opt3.addMouseListener(optionML);
popup.add(opt3);
}
public static void main(String[] args)
{
SwingUtilities.invokeLater(new Runnable()
{
#Override
public void run()
{
JPopupMenuIgnoreOptionCloseOnClick p = new JPopupMenuIgnoreOptionCloseOnClick();
p.setPreferredSize(new Dimension(400, 400));
JPanel contentPane = new JPanel();
contentPane.setBackground(Color.CYAN);
contentPane.add(p);
JFrame f = new JFrame();
f.setContentPane(contentPane);
f.setSize(800, 600);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setVisible(true);
}
});
}
}

I came across this problem myself when installing a custom JPopupMenu on a JCommandButton.
For your JCommandButton I found this to be helpful in preventing premature disposal of the parent popup:
this.putClientProperty(BasicCommandButtonUI.DONT_DISPOSE_POPUPS, true);
If what you are looking for is instead that upon making a JPopupMenu JMenuItem selection, the parent popup panel will stay open, you have a couple options. The problem stems from JPopupMenu's broken link in the ancestry container chain, on which the UI relies. Instead of getParent(), you need to return getInvoker().
1:
modify the library source in BasicPopupPanelUI.WindowTracker.eventDispatched(). Either change the SwingUtilities.getAncestorOfClass() calls to use SwingXUtilities.getAncestorOfClass() which accounts for this special case. Or implement the logic yourself.
if(parent instanceof JPopupMenu) parent = ((JPopupMenu)parent).getInvoker()
2:
Add this code to the widget (CustomButton?)
final JPopupMenu popper = new JPopupMenu(){ //hack
#Override public Container getParent(){
StackTraceElement ste = Thread.currentThread().getStackTrace()[2];
if(ste.getClassName().equals(SwingUtilities.class.getName()))
return CustomButton.this.getParent();
return super.getParent();
}
};
I chose #2, since I have issues with modifying 3rd party libraries.

How to prevent a disabled JMenuItem from hiding the menu when being clicked?

In my Java swing application i have noticed that when i click on a disabled JMenuItem in a JPopupMenu it hides the menu, but i i do not want to hide it, as if nothing is clicked. Is there a way to prevent this ?
-----------------------------------> Update: Added Code sample :
JMenuItem saveMenuItem = new JMenuItem();
saveMenuItem.setEnabled(false);
saveMenuItem.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
saveMenuItemActionPerformed();
}
});
add(saveMenuItem);
private void saveMenuItemActionPerformed() {
System.out.println( "Save clicked." );
}

This has been tested and works.
The Look & Feel decides how to handle the mouse events on disabled menu items. Anyway, you can intercept the undesired events by using a custom MenuItem. Simply use that code (copy/paste):
public class CustomMenuItem extends JMenuItem {
public CustomMenuItem(String text) {
super(text);
}
public CustomMenuItem() {
super();
}
protected void processMouseEvent(MouseEvent e) {
if (isEnabled()) super.processMouseEvent(e);
}
}
First, adapt the code to suit your needs (optional).
Finally, replace any JMenuItem with a CustomMenuItem.
That's it!

not sure how to prevent. but you can setVisible(false) to prevent it being displayed. Also if a user clicks on the disable menu no action will take place.

When you are disabling JMenuItem, you should remove the ActionListener associated with that JMenuItem by using
jMenuItem.removeActionListener() method.
If u remove that that action will not call the listener and popup will not be disappeared.
I hope this will help to achieve your target.

did you gave a try at this method:
http://download.oracle.com/javase/6/docs/api/javax/swing/JMenuItem.html#setArmed%28boolean%29
"arm the menu item so it can be selected", which I guess would do the trick if set to false.

In short, you can do this, but you will have to write your own mouse listener, which may require a lot of copy&paste from the jdk source code, which is not a very good idea, and I'm not sure about what license restrictions it will put on your code.
I would start digging from this method:
javax.swing.plaf.basic.BasicMenuItemUI.Handler#mouseReleased
which seems to be the entry point from where the menu handling mechanism hides the popup. I would take a closer look at
javax.swing.plaf.basic.BasicPopupMenuUI.MouseGrabber#stateChanged
EDIT Developing answer by #Burhan Valikarimwala, try this apporach: remove all action listeners from the disabled JMenuItem and store them in some static temp structure (let's say a Map<WeakReference<JMenuItem>, List<MouseListener>>), this way it will not hide the popup. When you make the menu item enabled again, add all the listeners back. Make it into some util method and it will be seamless.

The only solution I could come up with, for your problem of a click on disable JMenuItem causing it to hide is below:
import java.awt.Color;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import javax.swing.JFrame;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JPopupMenu;
public class PopupMenuDisableNoCloseTest extends JPanel implements ActionListener
{
public static void main(String[] args)
{
PopupMenuDisableNoCloseTest p = new PopupMenuDisableNoCloseTest();
p.setPreferredSize(new Dimension(200, 300));
p.setBackground(Color.GREEN);
JPanel contentPane = new JPanel();
contentPane.add(p);
final JFrame f = new JFrame();
final JPopupMenu popup = new JPopupMenu();
final JMenuItem menuItem1 = new JMenuItem("A popup menu item");
menuItem1.addActionListener(p);
menuItem1.addMouseListener(new MouseAdapter()
{
#Override
public void mousePressed(MouseEvent e)
{
System.out.println(" menuItem1 mousePressed e.getPoint()=" + e.getPoint());
}
#Override
public void mouseReleased(MouseEvent e)
{
System.out.println(" menuItem1 mouseReleased e.getPoint()=" + e.getPoint());
if(!menuItem1.isEnabled())
popup.setVisible(true);
}
});
menuItem1.setEnabled(false);
popup.add(menuItem1);
JMenuItem menuItem2 = new JMenuItem("Another popup menu item");
menuItem2.addActionListener(p);
popup.add(menuItem2);
MouseListener popupListener = new PopupListener(popup);
f.addMouseListener(popupListener);
f.setContentPane(contentPane);
f.setSize(800, 600);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setVisible(true);
}
#Override
public void actionPerformed(ActionEvent e)
{
JMenuItem source = (JMenuItem) (e.getSource());
String s = "Action event detected. Event source: " + source.getText();
System.out.println("s=" + s);
}
static class PopupListener extends MouseAdapter
{
JPopupMenu popup;
PopupListener(JPopupMenu popupMenu)
{
popup = popupMenu;
}
#Override
public void mousePressed(MouseEvent e)
{
maybeShowPopup(e);
}
#Override
public void mouseReleased(MouseEvent e)
{
maybeShowPopup(e);
}
private void maybeShowPopup(MouseEvent e)
{
if(e.isPopupTrigger())
{
popup.show(e.getComponent(),
e.getX(), e.getY());
}
}
}
}
Basically the hiding happens when your release is inside the bounds of the JMenuItem, therefore we are checking if it is disabled then we show popup again. As by this time it is already decided that it will be hidden. I was trying calling super.mouseRelease with a different MouseEvent pointing outside component and consuming the previous one but it helps nothing.
Anyway this solution works.
Enjoy, Boro

I think in Java7 this has been fixed.