Develop Reference

Implementing a JMenu with actionPerformed using TextAction

I have a Java Swing interface with multiple JTextArea's and I am implementing an "Edit" menu with various different functions like "Find", "Copy", "Paste", etc. When I click on the JMenuItem I need to know which JTextArea had the focus which is achievable through a TextAction (I haven't gone down the route of a FocusListener and keeping track of what last had the focus):
JMenuItem miFind = new JMenuItem(new EditHandler("Find"));
class EditHandler extends TextAction {
private String s = null;
public EditHandler(String vs) {
super(vs);
s = vs;
}
#Override
public void actionPerformed(ActionEvent e) {
JTextComponent c = getFocusedComponent();
if (s.equals("Find")) {
showFindDialog(c);
}
}
}
This works well and good but I want to be able to disable the "Find" JMenuItem under certain contexts (i.e. if the specific JTextArea is disabled or is empty. I can implement an ActionListener on a JMenu but I can't use getFocusedComponent() to identify what JTextArea has the focus.
According to the Java docs the JMenu constructor takes an Action (like a JMenuItem) and I have tried the following:
mEdit = new JMenu(new EditHandler("Edit"));
However, although the constructor fires, the actionPerformed() event isn't firing within my EditHandler for the JMenu. If I can get it to fire then I was planning to either enable or disable my "Find" JMenuItem.

The best way for you is using of actions map of the text component to place the corresponding action. In this case you can disable it for some text components.
#Override
public void actionPerformed(ActionEvent e) {
JTextComponent c = getFocusedComponent();
if (s.equals("Find")) {
Action a = c.getActionMap().get("Find");
if (a.isEnabled()) {
// generate new event to modify the source (menu item -> text component)
ActionEvent ae = new ActionEvent(c, e.getID(), e.getCommand());
a.actionPerformed(ae);
}
}
}
For each your text component you must provide an action and register it using the action map of the component.
public class UniversalFindAction extends AbstractAction {
public void actionPerformed(ActionEvent ae) {
JTextComponent c = (JTextComponent) ae.getSource();
showFindDialog(c);
}
}
// registering of action
JTextComponent comp = new JTextArea();
comp.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW).put(KeyStroke.getKeyStroke(KeyEvent.VK_F, InputEvent.CTRL_DOWN_MASK), "Find");
comp.getActionMap().put("Find", new UniversalFindAction());

Thanks to #sergiy-medvynskyy I have implemented a Global Focus Listener to keep track of the last JTextArea to be focused:
KeyboardFocusManager.getCurrentKeyboardFocusManager().addPropertyChangeListener("permanentFocusOwner", new PropertyChangeListener() {
#Override
public void propertyChange(final PropertyChangeEvent e) {
if (e.getNewValue() instanceof JTextArea) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
tFocused = (JTextArea)e.getNewValue();
}
});
}
}
});
I then check the tFocused object using a MenuListener on my JMenu to verify what JTextArea currently has the focus. I can then call setEnabled() on my respective JMenuItem's depending on the context.

Java jpopupmenu on mouseExited

I'm trying to create system tray icon with two popup menus, one should be called with left mouse button and another with right. AWT offers simple way to create PopupMenu but it's not posible to call menu with left mouse button without making invisible JFrame or something. So, I find out that swing JPopupMenu can be called by any of mouse buttons. But JPopupMenu have bug (I don't know if this is really a bug or I'm not so good in Java) that it's not hiding when I press mouse outside JPopupMenu. I've tried to use mouse listener's function mouseExited, but it works only on JPopupMenu border. If mouse leaves JPopupMenu border it hides and I can't press any of JPopupMenu buttons. Maybe, anyone had the same problem and could help me find out how to make it work right.
public static JPopupMenu jpm;
public static TrayIcon ti;
public static void main(String args[]) throws IOException, AWTException,
ClassNotFoundException, InstantiationException,
IllegalAccessException, UnsupportedLookAndFeelException {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
SystemTray st = SystemTray.getSystemTray();
Image icon = ImageIO.read(SipLogin.class
.getResource("/resources/phone-yellow-small.png"));
ti = new TrayIcon(icon, "Sip login", null);
jpm = new JPopupMenu();
JMenuItem jmi1 = new JMenuItem("JMenuItem1");
JMenuItem jmi2 = new JMenuItem("JMenuItem2");
JMenuItem jmi3 = new JMenuItem("JMenuItem3");
JMenuItem jmi4 = new JMenuItem("JMenuItem4");
ti.addMouseListener(new MouseAdapter() {
public void mouseReleased(MouseEvent e) {
if (e.isPopupTrigger()) {
jpm.setLocation(e.getX(), e.getY());
jpm.setInvoker(jpm);
jpm.setVisible(true);
}
}
});
jpm.add(jmi1);
jpm.add(jmi2);
jpm.add(jmi3);
jpm.add(jmi4);
jpm.addMouseListener(new MouseAdapter() {
public void mouseExited(MouseEvent e) {
jpm.setVisible(false);
}
});
st.add(ti);
}

Take that one mouse listener and separate the left and right click:
Change from
ti.addMouseListener(new MouseAdapter() {
public void mouseReleased(MouseEvent e) {
if (e.isPopupTrigger()) {
jpm.setLocation(e.getX(), e.getY());
jpm.setInvoker(jpm);
jpm.setVisible(true);
}
}
});
to
ti.addMouseListener(new MouseAdapter() {
public void mouseReleased(MouseEvent e) {
if(e.getclickCount < 2){
if(e.getButton().equals(MouseEvent.Button1){
showPopup1();
}
if(e.getButton().equals(MouseEvent.Button3){
showPopup2();
}
}
}
});

thanks for very useful conversation, but I need to add some words:
Sometimes when you add menuItems the JPopupMenu behaves in unpredictable manner (it is not closed, when you mouseover your mouse from it).
In this case you need to delete the mouse motion listeners from your menu items
JMenuItem jmi1 = new JMenuItem("JMenuItem1");
jmi1.removeMouseMotionListener(jmi1.getMouseMotionListeners()[0]);
jmi1.removeMouseListener(jmi1.getMouseListeners()[0]);

How do I make a JPopupMenu appear when any one of 3 JButtons is clicked, right-clicked, or dragged upon?

I am trying to make a set of navigation buttons for a file browser. I want it so that if the user clicks the dedicated history button, a JPopupMenu appears. However, I also want that exact same menu to appear when the user right-clicks or drags the cursor down the back or forward button. How can I make that exact same JPopupMenu (not a copy, but the same exact one) appear for multiple GUI components for different gestures?
So far I've tried the following:
histButton.addMouseListener(new MouseAdapter()
{
#Override public void mouseClicked(MouseEvent e)
{
showPopup(e);
}
#Override public void mouseDragged(MouseEvent e)
{
showPopup(e);
}
private void showPopup(MouseEvent e)
{
histPopupMenu.show(e.getComponent(), e.getX(), e.getY());
}
});
forwardButton.addMouseListener(new MouseAdapter()
{
#Override public void mouseClicked(MouseEvent e)
{
if (e.isPopupTrigger())
showPopup(e);
}
#Override public void mouseDragged(MouseEvent e)
{
showPopup(e);
}
private void showPopup(MouseEvent e)
{
histPopupMenu.show(e.getComponent(), e.getX(), e.getY());
}
});
backButton.addMouseListener(new MouseAdapter()
{
#Override public void mouseClicked(MouseEvent e)
{
if (e.isPopupTrigger())
showPopup(e);
}
#Override public void mouseDragged(MouseEvent e)
{
showPopup(e);
}
private void showPopup(MouseEvent e)
{
histPopupMenu.show(e.getComponent(), e.getX(), e.getY());
}
});
All components are added and display correctly, and debugging shows me that they register the events, but no menu appears.

Bringing Up a Popup Menu shows the traditional implementation using mousePressed(), mouseReleased() and isPopupTrigger(). Note that "The exact gesture that should bring up a popup menu varies by look and feel." You might compare what's shown with your implementation, which uses mousePressed().
Addendum: For reference, #mKorbel recalls this client property that may prove useful.
import java.awt.Component;
import java.awt.event.*;
import javax.swing.*;
/** #author mKorbel */
public class ComboBoxAction extends JFrame implements ActionListener {
private static final long serialVersionUID = 1L;
private JComboBox comboBox;
private JFrame frame;
public ComboBoxAction() {
comboBox = new JComboBox();
comboBox.addActionListener(this);
comboBox.addItem("Item 1");
comboBox.addItem("Item 2");
comboBox.addItem("Item 3");
comboBox.addItem("Item 4");
for (Component component : comboBox.getComponents()) {
if (component instanceof AbstractButton) {
if (component.isVisible()) {
comboBox.remove(component);
}
}
}
//This prevents action events from being fired when the
//up/down arrow keys are used on the dropdown menu
comboBox.putClientProperty("JComboBox.isTableCellEditor", Boolean.TRUE);
comboBox.firePopupMenuWillBecomeVisible();
frame = new JFrame();
frame.add(comboBox);
frame.setDefaultCloseOperation(EXIT_ON_CLOSE);
frame.pack();
frame.setVisible(true);
}
#Override
public void actionPerformed(ActionEvent e) {
System.out.println(comboBox.getSelectedItem());
//make sure popup is closed when 'isTableCellEditor' is used
comboBox.hidePopup();
}
public static void main(String[] args) {
java.awt.EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
new ComboBoxAction();
}
});
}
}

How to make a JMenu have Button behaviour in a JMenuBar

I was trying to make a JMenu behave like a JButton but I'm having some problems and hopefully someone here can help!
I've added a MenuListener to the JMenu item with this but I cant get the popup menu/focus to leave to enable me to properly click the JMenu repeated times to trigger this function and i was hoping someone could tell me what i'm doing wrong. Thanks.
public void menuSelected(MenuEvent e)
{
... // do stuff here code
JMenu source = (JMenu)e.getSource();
source.setSelected(false);
source.setPopupMenuVisible(false);
}

Not completely sure what you're asking...
But JMenuBar inherits from Container - if you'd rather add a JButton to it than a JMenu you can simply call -
JMenuBar menuBar = ....
JButton myButton = ....
menuBar.add(myButton);

This code sample runs in eclipse, Again concerned about how you are using it?
public class MyMenuFrame extends JFrame {
public MyMenuFrame() throws HeadlessException {
super("My Frame");
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setSize(400, 300);
Container pane = this.getContentPane();
pane.setLayout(new BorderLayout());
pane.add(new JLabel("Hi there"), BorderLayout.PAGE_START);
this.setVisible(true);
JMenuBar menubar = new JMenuBar();
JMenu menu = new JMenu("File");
menu.addMenuListener(new MenuListener() {
#Override
public void menuSelected(MenuEvent e) {
System.out.println("a");
}
#Override
public void menuDeselected(MenuEvent e) {
System.out.println("a");
}
#Override
public void menuCanceled(MenuEvent e) {
System.out.println("a");
}
});
menubar.add(menu);
this.setJMenuBar(menubar );
}
public static void main(String[] args) {
new MyMenuFrame();
}
}

I know this is an old thread, but I think I might have a solution. I stumbled accross this problem in one of my apps, and found a workaround. Try using a JMenuItem instead of a JMenu. It will have the same L&F as a JMenu when you attach it to a JMenuBar. The only thing you have to do is set the size of your new "button", as your Layout Manager (even if you have not set one) will resize this component based on its own rules:
http://www.javaworld.com/javaworld/jw-09-2000/jw-0922-javatraps.html
The way to do it is found under that link (if you feel uncomfortable clicking on the link, google for "setsize doesnt work" - it will be the in the top ten results). If you do not set the size properly, your new "button" will fill up the remaining space of your JMenuBar.
try this code:
menuItem.setMinimumSize(someMenu.getSize());
menuItem.setPreferredSize(someMenu.getSize());
menuItem.setMaximumSize(someMenu.getSize());
menuItem.setActionCommand("ActionText");
setActionCommand() method will set an action command, so that when you click your new "button" this will be the action command passed by the action event argument to the action performed method, so that you can easily identify it:
public void actionPerformed(ActionEvent e) {
System.out.println(e.getActionCommand());
}
Hope this helps!

It's very difficult to determine what you're trying to do here. But I don't think you are properly using JMenu.
A JMenu is the object that represents a Menu. It is separate from the menu bar (JMenuBar) and from the menu item (JMenuItem). A JMenuBar usually contains multiple JMenus (File, Edit, etc) which in turn contain multiple JMenuItems (New, Open, Close). The JMenuItems are what is clicked and "acts like a button" in the menu.
To get a menu item to act like a button, simply add it to the menu. For example:
JMenu fileMenu = new JMenu("File");
JMenuItem newChoice = new JMenuItem("New");
newChoice.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent evt) {
newHasBeenSelected();
}
});
fileMenu.add(newChoice);
If you're trying to create a pop-up menu, you need to use JPopupMenu instead of JMenu, and you don't need a JMenuBar. Here are the Java tutorials on menus: http://java.sun.com/docs/books/tutorial/uiswing/components/menu.html
And here are the Java docs for JMenuBar, JMenu, JPopupMenu, and JMenuItem.
If you edit your question and give a more detailed explanation of what you're doing I might be able to give more specific help.

Ok I decided to investigate this a bit more and The following is the reslut and appears to act just like a JButton but appears like a jmenu on a jmenubar. Code below. (note just adding an actionListener to a JMenu didnt work right which is the reason for the mouselistener. You add an actionListener to the menubutton just like a normal button and as long as you dont add any menuitems to the menubutton (which technically you could) it will appear as a JMenu on the JMenuBar but behave like a button.
import java.awt.Component;
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 java.lang.reflect.Method;
import java.util.EventListener;
import javax.swing.ImageIcon;
import javax.swing.JMenu;
public class MenuButton extends JMenu {
private boolean startedIn = false;
private ActionListener action;
public MenuButton(String title) {
super(title);
removeListeners(this);
this.addMouseListener(new MenuButtonListener());
}
public MenuButton(ImageIcon icon) {
super();
removeListeners(this);
this.addMouseListener(new MenuButtonListener());
this.setIcon(icon);
}
public void addActionListener(ActionListener a) {
action = a;
}
//we need to remove all the listeners already associated with a JMenu. If we do
//not do this, then it will not behave as expected because some mouseclicks are eaten
//by these listeners. There is no easy way to do that, the following method is a
//workaroundprovided in the java bug database.
static private void removeListeners(Component comp) {
Method[] methods = comp.getClass().getMethods();
for (int i = 0; i < methods.length; i++) {
Method method = methods[i];
String name = method.getName();
if (name.startsWith("remove") && name.endsWith("Listener")) {
Class[] params = method.getParameterTypes();
if (params.length == 1) {
EventListener[] listeners = null;
try {
listeners = comp.getListeners(params[0]);
} catch (Exception e) {
// It is possible that someone could create a listener
// that doesn't extend from EventListener. If so, ignore
// it
System.out.println("Listener " + params[0]
+ " does not extend EventListener");
continue;
}
for (int j = 0; j < listeners.length; j++) {
try {
method.invoke(comp, new Object[] { listeners[j] });
// System.out.println("removed Listener " + name +
// " for comp " + comp + "\n");
} catch (Exception e) {
System.out
.println("Cannot invoke removeListener method "
+ e);
// Continue on. The reason for removing all
// listeners is to
// make sure that we don't have a listener holding
// on to something
// which will keep it from being garbage collected.
// We want to
// continue freeing listeners to make sure we can
// free as much
// memory has possible
}
}
} else {
// The only Listener method that I know of that has more
// than
// one argument is removePropertyChangeListener. If it is
// something other than that, flag it and move on.
if (!name.equals("removePropertyChangeListener"))
System.out.println(" Wrong number of Args " + name);
}
}
}
}
public class MenuButtonListener extends MouseAdapter {
boolean within = false;
boolean pressed = false;
public void mousePressed(MouseEvent e) {
MenuButton.this.setSelected(true);
pressed = true;
//System.out.println("pressed");
}
public void mouseReleased(MouseEvent e) {
//System.out.println("released");
MenuButton.this.setSelected(false);
if (action != null && within && pressed) {
action.actionPerformed(new ActionEvent(this,
ActionEvent.ACTION_PERFORMED, null));
MenuButton.this.setSelected(false);
}
pressed = false;
}
#Override
public void mouseEntered(MouseEvent e) {
within = true;
}
#Override
public void mouseExited(MouseEvent e) {
within = false;
}
}
}

How to change the jtooltip timers for 1 component

I have a component where i want to display a custom jtooltip. That is easy, just change the getTooltip method. Similar for location and text.
However i also want to change the timers. The tooltip should always be displayed if the mouse is over a cellrenderer of the component. If it leaves all of those it should be turned invisible.
I know that i can use TooltipManager to control the times globally. But the best solution is probably to just shortcircut that and display the tooltip myself with a mouselistener. However when i tried to do that (unregister the component in TooltipManager and setting the tooltip visible, with text and in the correct position, in a mouse listener) the tooltip never showed at all. What am i doing wrong?
Edit:
Now the question has changed! Into 2 questions.
My solution is for now this, however it losses the shadow that the jtooltip always displays sometimes frustratingly, and it is hidden if the mouse exits into the popup itself. How to filter the mouseexit events over the popup if the popup is not even a component? I could do some hacking based on the lastPosition, but that seems stupid, since i don't really know its width.
private Popup lastPopup;
private final JToolTip tooltip = ...;
private Point lastPoint;
#Override public void mouseMoved(MouseEvent e) {
Point p = privateToolTipLocation(e);
if (p == null || p.equals(lastPoint)) {
return;
}
lastPoint = p;
tooltip.setTipText(privateToolTipText(e));
//copy
p = new Point(p);
SwingUtilities.convertPointToScreen(p, this);
Popup newPopup = PopupFactory.getSharedInstance().getPopup(this, tooltip, p.x, p.y);
if (lastPopup != null) {
lastPopup.hide();
}
lastPopup = newPopup;
newPopup.show();
}
#Override public void mouseExited(MouseEvent e) {
if (lastPopup != null && someUnknownCondiction) {
lastPopup.hide();
lastPopup = null;
}
}

Rather than trying to reimplement the display of tooltips, you could add a mouse listener to your component that changes the global tooltip timer when the mouse enters and leaves the region above the component.
Here is some example code:
instantTooltipComponent.addMouseListener(new MouseAdapter()
{
final int defaultTimeout = ToolTipManager.sharedInstance().getInitialDelay();
#Override
public void mouseEntered(MouseEvent e) {
ToolTipManager.sharedInstance().setInitialDelay(0);
}
#Override
public void mouseExited(MouseEvent e) {
ToolTipManager.sharedInstance().setInitialDelay(defaultTimeout);
}
});
This should change the tooltip delay to zero whenever the mouse moves over your component and change it back to the default delay whenever the mouse moves off of your component.

But the best solution is probably to
just shortcircut that and display the
tooltip myself with a mouselistener
Invoke the default Action for the component to display the tooltip:
Action toolTipAction = component.getActionMap().get("postTip");
if (toolTipAction != null)
{
ActionEvent postTip = new ActionEvent(component, ActionEvent.ACTION_PERFORMED, "");
toolTipAction.actionPerformed( postTip );
}
Edit:
Above code doesn't appear to work anymore. Ctrl+F1 is the default KeyStroke used to display the tool tip of a component. So an alternative approach is to dispatch the Ctrl+F1 KeyStroke to the component. For example:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class PostTipSSCCE2 extends JPanel
{
public PostTipSSCCE2()
{
FocusAdapter fa = new FocusAdapter()
{
public void focusGained(FocusEvent e)
{
JComponent component = (JComponent)e.getSource();
KeyEvent ke = new KeyEvent(
component,
KeyEvent.KEY_PRESSED,
System.currentTimeMillis(),
KeyEvent.CTRL_MASK,
KeyEvent.VK_F1,
KeyEvent.CHAR_UNDEFINED);
component.dispatchEvent( ke );
}
};
MouseAdapter ma = new MouseAdapter()
{
#Override
public void mouseEntered(MouseEvent e)
{
JComponent component = (JComponent)e.getSource();
KeyEvent ke = new KeyEvent(
component,
KeyEvent.KEY_PRESSED,
System.currentTimeMillis(),
KeyEvent.CTRL_MASK,
KeyEvent.VK_F1,
KeyEvent.CHAR_UNDEFINED);
component.dispatchEvent( ke );
}
};
JButton button = new JButton("Button");
button.setToolTipText("button tool tip");
button.addFocusListener( fa );
button.addMouseListener( ma );
add( button );
JTextField textField = new JTextField(10);
textField.setToolTipText("text field tool tip");
textField.addFocusListener( fa );
textField.addMouseListener( ma );
add( textField );
JCheckBox checkBox = new JCheckBox("CheckBox");
checkBox.setToolTipText("checkbox tool tip");
checkBox.addFocusListener( fa );
checkBox.addMouseListener( ma );
add( checkBox );
}
private static void createAndShowUI()
{
JFrame frame = new JFrame("PostTipSSCCE2");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add( new JScrollPane(new PostTipSSCCE2()) );
frame.pack();
frame.setLocationByPlatform( true );
frame.setVisible( true );
}
public static void main(String[] args)
{
EventQueue.invokeLater(new Runnable()
{
public void run()
{
createAndShowUI();
}
});
}
}

Apparently what controls the display of the Tooltip is if the getTooltipText returns null or not. Having that to null, eliminated a npe and allowed things to display. However there are some artifacts still..