I am trying to create a JMenuItem that is disabled by default, but a method can be called to enable it. Just for the moment whilst I'm testing out my code, I want the method to be called when I click on another menu item. I have had a look at the documentation for JMenuItem, but I'm pretty new to Java and I'm having trouble finding exactly what I need. I've tried using the updateUI() command, but I that hasn't worked, so I'm totally stuck. Thanks in advance for any help :)
This is what I have so far:
public class initialScreen extends JFrame implements ActionListener{
Dimension screenSize = new Dimension(800,600);
JMenuItem runE, newP;
public initialScreen(){
super("Experiment Control Suite");
setSize(screenSize);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JMenuBar bar = new JMenuBar();
JMenuItem newP = new JMenuItem("New");
newP.addActionListener(this);
runE = new JMenuItem("Run");
runE.setEnabled(false);
runE.addActionListener(this);
JMenu exp = new JMenu("Experiment");
exp.add(runE);
JMenu par = new JMenu("Participant");
par.add(newP);
bar.add(exp);
bar.add(par);
setJMenuBar(bar);
setVisible(true);
}
public void enableRun(){
runE.setEnabled(true);
runE.updateUI();
}
public void actionPerformed(java.awt.event.ActionEvent e){
if(e.getSource() == newP) {
enableRun();
}
else if(e.getSource() == runE) {
System.out.println("run has been clicked");
}
}
}
Your method enableRun is never invoked because of the following line:
JMenuItem newP = new JMenuItem("New");
Instead, refactor it as such,
newP = new JMenuItem("New");
Now, the field will be correctly initialized and registered as an ActionListener. And thus, when checking the source, enableRun will be invoked and the menu item will be enabled.
Note that in this case, updateUI is completely unnecessary (I suggest you read the javadoc to learn its purpose).
Related
My notepad program that I'm writing uses AbstractActions for each item in the JMenuBar, and I want to keep it consistent that way throughout my code. And now I'm implementing Cut, Copy, Paste into the program but I'm unsure of how to do that with Action.
import java.awt.*;
import java.awt.event.ActionEvent;
import javax.swing.*;
import javax.swing.text.DefaultEditorKit;
public class Home {
static Action Cut = new AbstractAction("Cut-Action") {
public void actionPerformed(ActionEvent e) {
// Where I want to use cut
new DefaultEditorKit.CutAction();
}
};
static public JMenuBar createMenuBar() {
JMenuBar menuBar = new JMenuBar();
JMenu menu = new JMenu("Edit");
menu.add(Cut); // Adds the cut action
// adds the non-action method
JMenuItem item = new JMenuItem(new DefaultEditorKit.CutAction());
item.setText("Cut-NonAction");
menu.add(item);
menuBar.add(menu);
return menuBar;
}
public static void main(String[] args) {
JFrame frame = new JFrame("Home");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JMenuBar menuBar = createMenuBar();
frame.add(menuBar, BorderLayout.NORTH);
JTextPane txt = new JTextPane();
JScrollPane s = new JScrollPane(txt);
frame.add(s, BorderLayout.CENTER);
frame.setSize(400, 300);
frame.setVisible(true);
}
}
How would I be able to use the cut action in my abstract action??
I figured it out with a little bit of trial and error.
I changed this code:
public void actionPerformed(ActionEvent e) {
new DefaultEditorKit().CutAction();
}
to:
public void actionPerformed(ActionEvent e) {
Action cut = new DefaultEditorKit.CutAction();
cut.actionPerformed(e);
}
How would I be able to use the cut action in my abstract action??
Why are you trying to do this? The is not the way to use the Actions from the editor kit.
This is the proper way to use the actions:
JMenuItem item = new JMenuItem(new DefaultEditorKit.CutAction());
Or if you happen to need the CutAction on a menu and on a toolbar you would use code like:
Action cut = new DefaultEditorKit.CutAction();
cut.putValue(Action.NAME, "Cut");
JMenuItem cutMenuItem = new JMenuItem( cut );
JButton cutButton = new JButton( cut );
Now the same Action is shared which means you can enable/disable the Action and both components will be affected. Read the section from the Swing tutorial on How to Use Actions for more information and examples.
I am a beginner using GWT. I have a menubar which I want to retain on the screen even if the mouse is not over it. However when the mouse is not over the menubar and clicked somewhere on the screen then I want the menubar to disappear. I tried using the MouseOutEvent but I need it to fire only when the mouse is clicked not just out. Any help would be appreciated.
this.menu.addDomHandler(menuHoverOutHandler, MouseOutEvent.getType());
MouseOutHandler menuHoverOutHandler = new MouseOutHandler() {
public void onMouseOut(MouseOutEvent event) {
Window.alert("I am outside the region");
}
};
Below is a fully working answer taken from my live app:
The way I solved the menu close on mouse out was to run a boolean variable "isMouseOut" in the top of the constructor to keep track, and then allocate the MouseListener in a more OO friendly way to keep track of the multiple MouseIn-MouseOut events as a user interacts with the menu. Which calls a separate menuClear method acting upon the state of the boolean "isMouseOut". The class implements MouseListener. This is how its done.
Create an ArrayList adding all the menu items to this array first. Like so:
Font menuFont = new Font("Arial", Font.PLAIN, 12);
JMenuBar menuBar = new JMenuBar();
getContentPane().add(menuBar, BorderLayout.NORTH);
// Array of MenuItems
ArrayList<JMenuItem> aMenuItms = new ArrayList<JMenuItem>();
JMenuItem mntmRefresh = new JMenuItem("Refresh");
JMenuItem mntmNew = new JMenuItem("New");
JMenuItem mntmNormal = new JMenuItem("Normal");
JMenuItem mntmMax = new JMenuItem("Max");
JMenuItem mntmStatus = new JMenuItem("Status");
JMenuItem mntmFeedback = new JMenuItem("Send Feedback");
JMenuItem mntmEtsyTWebsite = new JMenuItem("EtsyT website");
JMenuItem mntmAbout = new JMenuItem("About");
aMenuItms.add(mntmRefresh);
aMenuItms.add(mntmNew);
aMenuItms.add(mntmNormal);
aMenuItms.add(mntmMax);
aMenuItms.add(mntmStatus);
aMenuItms.add(mntmFeedback);
aMenuItms.add(mntmEtsyTWebsite);
aMenuItms.add(mntmAbout);
then iterate over the arrayList at this stage adding a MouseListener using the for() loop:
for (Component c : aMenuItms) {
if (c instanceof JMenuItem) {
c.addMouseListener(ml);
}
}
Now set JMenu parents for the MenuBar:
// Now set JMenu parents on MenuBar
final JMenu mnFile = new JMenu("File");
menuBar.add(mnFile).setFont(menuFont);
final JMenu mnView = new JMenu("View");
menuBar.add(mnView).setFont(menuFont);
final JMenu mnHelp = new JMenu("Help");
menuBar.add(mnHelp).setFont(menuFont);
Then add the dropdown menuItems children to the JMenu parents:
// Now set menuItems as children of JMenu parents
mnFile.add(mntmRefresh).setFont(menuFont);
mnFile.add(mntmNew).setFont(menuFont);
mnView.add(mntmNormal).setFont(menuFont);
mnView.add(mntmMax).setFont(menuFont);
mnHelp.add(mntmStatus).setFont(menuFont);
mnHelp.add(mntmFeedback).setFont(menuFont);
mnHelp.add(mntmEtsyTWebsite).setFont(menuFont);
mnHelp.add(mntmAbout).setFont(menuFont);
Add the mouseListeners to the JMenu parents as a separate step:
for (Component c : menuBar.getComponents()) {
if (c instanceof JMenu) {
c.addMouseListener(ml);
}
}
Now that the child menuItem elements all have their own listeners that are separate to the parent JMenu elements and the MenuBar itself - It is important to identify the object type within the MouseListener() instantiation so that you get the menu auto opening on mouseover (in this example the 3x JMenu parents) BUT ALSO avoids child exception errors and allows clean identification of mouseOUT of the menu structure without trying to monitor where the mouse position is. The MouseListener is as follows:
MouseListener ml = new MouseListener() {
public void mouseClicked(MouseEvent e) {
}
public void mousePressed(MouseEvent e) {
}
public void mouseReleased(MouseEvent e) {
}
public void mouseExited(MouseEvent e) {
isMouseOut = true;
timerMenuClear();
}
public void mouseEntered(MouseEvent e) {
isMouseOut = false;
Object eSource = e.getSource();
if(eSource == mnHelp || eSource == mnView || eSource == mnFile){
((JMenu) eSource).doClick();
}
}
};
The above only simulates the mouse click into the JMenu 'parents' (3x in this example) as they are the triggers for the child menu dropdowns. The timerMenuClear() method calls on the MenuSelectionManager to empty whatever selectedpath point was live at the time of real mouseOUT:
public void timerMenuClear(){
ActionListener task = new ActionListener() {
public void actionPerformed(ActionEvent e) {
if(isMouseOut == true){
System.out.println("Timer");
MenuSelectionManager.defaultManager().clearSelectedPath();
}
}
};
//Delay timer half a second to ensure real mouseOUT
Timer timer = new Timer(1000, task);
timer.setInitialDelay(500);
timer.setRepeats(false);
timer.start();
}
It took me a little testing, monitoring what values I could access within the JVM during its development - but it Works a treat! even with nested menus :) I hope many find this full example very useful.
Use widget's blur handler. It detects when the widget lost focus.
can i call actionperformed method with jmenu using swing
i am using the following code
JMenu menu1= new JMenu("File");
MenuBar mb= new MenuBar();
mb.add(menu1);
set JmenuBar(mb)
menu1.addActionListener(this);
public void actionPerformed(ActionEvent ae)
{
JOptionPane.showMessaageDialog(null,"menu clicked");
// but its not working
}
thanks in Advance
The action a JMenu is designed to perform is to open a popup with JMenuItems, it doesn't support doing anything else (and even if it did, it would confuse your users). Custom actions are supposed to be handled by JMenuItems in the popup. Install them with something like:
JMenu menu ..
Action myAction = new AbstractAction("Do XY") {
public void actionPerformed(..) {
// implement doing XY
}
};
menu.add(myAction);
I've got a new UI I'm working on implementing in Java and I'm having trouble implementing a JPopupMenu containing a JMenu (as well as several JMenuItems), which itself contains several JMenuItems. The JPopupMenu appears where I click the RMB, and it looks good, but the "Connect" JMenu doesn't seem to have any children when I mouse-over, despite my best efforts to .add() them.
Having looked at several examples online, I haven't seen any that specifically implement a listener for mouseEntered() to roll out the sub-items. I'm of a mind that I'm messing something up in my menu initialization method.
I've attached the pertinent code for your perusal.
//Elsewhere...
private JPopupMenu _clickMenu;
//End Elsehwere...
private void initializeMenu()
{
_clickMenu = new JPopupMenu();
_clickMenu.setVisible(false);
_clickMenu.add(generateConnectionMenu());
JMenuItem menuItem;
menuItem = new JMenuItem("Configure");
addMenuItemListeners(menuItem);
_clickMenu.add(menuItem);
menuItem = new JMenuItem("Status");
addMenuItemListeners(menuItem);
_clickMenu.add(menuItem);
}
private JMenu generateConnectionMenu()
{
JMenu menu = new JMenu("Connect");
List<Port> portList = _database.getAllPortsInCard(_cardId);
for(int i = 0; i < portList.size(); i++)
{
menu.add(new JMenuItem(portList.get(i).getName()));
}
return menu;
}
The code is certainly not the prettiest, but go easy on me as it's been altered too many times today as time permitted while I tried to figure out why this wasn't working. I'm thinking it may be a question of scope, but I've tried a few different code configurations to no avail. Feel free to ask any followup questions or smack me for an obvious oversight (it's happened before...). Thanks all!
Edit:
Chalk this one up to a lack of experience with Java and Swing... I was manually positioning and making the JPopupMenu visible instead of using the JComponent.setComponentPopupMenu(menu) method. After doing this for the card module in the above image (itself a JButton), the submenu displays correctly. A different, functional version of the initialization code is included below.
private void initializeMenu()
{
_cardMenu = new JPopupMenu();
JMenu menu = new JMenu("Connect");
JMenuItem menuItem;
menuItem = new JMenuItem("1");
menu.add(menuItem);
menuItem = new JMenuItem("2");
menu.add(menuItem);
_cardMenu.add(menu);
_cardMenu.add(new JMenuItem("Configure"));
_cardMenu.add(new JMenuItem("Status"));
_mainButton.setComponentPopupMenu(_cardMenu); //Important, apparently!
}
So, lesson learned. Thanks for the help guys!
This is common Bug or Swing property that in one moment can be visible only one Lightweight popup window, same issue is e.g. with popup from JComboBox added into JPopupMenu,
change Lightweight property to the Heavyweight
better would be
use un_decorated JDialog or JOptionPane with JComponents
EDIT #trashgod
everything works as I excepted, all JMenus, JMenuItems are visible and repeatly fired correct evets
code
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
public class ContextMenu implements ActionListener, MenuListener, MenuKeyListener {
private JTextArea textArea = new JTextArea();
public ContextMenu() {
final JPopupMenu contextMenu = new JPopupMenu("Edit");
JMenu menu = new JMenu("Sub Menu");
menu.add(makeMenuItem("Sub Menu Save"));
menu.add(makeMenuItem("Sub Menu Save As"));
menu.add(makeMenuItem("Sub Menu Close"));
menu.addMenuListener(this);
JMenu menu1 = new JMenu("Sub Menu");
menu1.add(makeMenuItem("Deepest Sub Menu Save"));
menu1.add(makeMenuItem("Deepest Sub Menu Save As"));
menu1.add(makeMenuItem("Deepest Sub Menu Close"));
menu.add(menu1);
menu1.addMenuListener(this);
contextMenu.add(menu);
contextMenu.add(makeMenuItem("Plain Save"));
contextMenu.add(makeMenuItem("Plain Save As"));
contextMenu.add(makeMenuItem("Plain Close"));
contextMenu.addMenuKeyListener(this);
JFrame frame = new JFrame();
JPanel panel = new JPanel();
panel.setLayout(new BorderLayout());
frame.add(panel);
panel.setComponentPopupMenu(contextMenu);
textArea.setInheritsPopupMenu(true);
panel.add(BorderLayout.CENTER, textArea);
JTextField textField = new JTextField();
textField.setInheritsPopupMenu(true);
panel.add(BorderLayout.SOUTH, textField);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(400, 200);
frame.setVisible(true);
}
#Override
public void actionPerformed(ActionEvent e) {
textArea.append(e.getActionCommand() + "\n");
}
private JMenuItem makeMenuItem(String label) {
JMenuItem item = new JMenuItem(label);
item.addActionListener(this);
return item;
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
ContextMenu contextMenu = new ContextMenu();
}
});
}
public void menuSelected(MenuEvent e) {
textArea.append("menuSelected" + "\n");
}
public void menuDeselected(MenuEvent e) {
textArea.append("menuDeselected" + "\n");
}
public void menuCanceled(MenuEvent e) {
textArea.append("menuCanceled" + "\n");
}
public void menuKeyTyped(MenuKeyEvent e) {
textArea.append("menuKeyTyped" + "\n");
}
public void menuKeyPressed(MenuKeyEvent e) {
textArea.append("menuKeyPressed" + "\n");
}
public void menuKeyReleased(MenuKeyEvent e) {
textArea.append("menuKeyReleased" + "\n");
}
}
I don't see an obvious problem in the code shown, although #mKorbel's point may apply. For reference, this ControlPanel adds a subMenu with several items.
I am making a simple java program that represents a Microsoft Word menu bar, and in the file menu I add an exit button... it does nothing.
I need your help to tell me what to do to make the exit button actually exit and close the program.
Here is my code:
public class MicrosoftWordMenu {
public static void main(String [] args)
{
JPanel panel = new JPanel();
JFrame frame = new JFrame("Microsoft Word");
JMenuBar bar = new JMenuBar();
JMenu menu = new JMenu("File");
JMenu menu1 = new JMenu("Edit");
JMenu menu2 = new JMenu("View");
JMenu menu3 = new JMenu("Insert");
JMenu menu4 = new JMenu("Format");
JMenu menu5 = new JMenu("Tools");
JMenu menu6 = new JMenu("Table");
JMenu menu7 = new JMenu("Window");
JMenu menu8 = new JMenu("Help");
frame.add(bar, BorderLayout.NORTH);
frame.add(panel);
bar.add(menu);
bar.add(menu1);
bar.add(menu2);
bar.add(menu3);
bar.add(menu4);
bar.add(menu5);
bar.add(menu6);
bar.add(menu7);
bar.add(menu8);
JMenuItem menuitem = new JMenuItem("New...");
JMenuItem menuitem1 = new JMenuItem("Open...");
JMenuItem menuitem2 = new JMenuItem("Close");
JMenuItem menuitem3 = new JMenuItem("Save");
JMenuItem menuitem4 = new JMenuItem("Save as...");
JMenuItem menuitem5 = new JMenuItem("Save as web page...");
JMenuItem menuitem6 = new JMenuItem("Web page preview ");
JMenuItem menuitem7 = new JMenuItem("Print ");
JMenuItem menuitem8 = new JMenuItem("Exit");
menu.add(menuitem);
menu.add(menuitem1);
menu.add(menuitem2);
menu.add(menuitem3);
menu.add(menuitem4);
menu.add(menuitem5);
menu.add(menuitem6);
menu.add(menuitem7);
menu.add(menuitem8);
frame.setSize(600,100);
frame.setVisible(true);
}
}
Also consider using Action to let components share functionality, as shown here.
Calling System.exit(0) on menu selection would do just fine.
At the moment you're just creating the GUI element, but they're basically empty shells. In particular, you've created items that appear on the menu, but you haven't added any behaviour to those items. (Since you haven't told your program anywhere what to do when an item is clicked, what did you think would happen)?
In order to provide this behaviour, you'll need to register an ActionListener, which will be called when something happens on an element, and will let you take an appropriate action at that point (such as calling System.exit(0). See the tutorial on Writing [Swing] Event listeners for details.
I always extend the AbstractAction class (which implements the ActionListener interface) which allows you to reuse your actions. By extending the AbstractAction, the actionPerformed(ActionEvent e) method will be invoked very time your button is clicked.
public class CloseAction extends AbstractAction {
public CloseAction() {
super("Close");
}
public actionPerformed(ActionEvent e) {
System.exit(1);
}
}
Now, to apply the above action to one of your buttons, you simply need to follow the below piece of code.
CloseButton.setAction(new CloseAction());
The close button will now shut down your application each time it gets pressed.
Use the ExitAction defined in Closing an Application. Then clicking on the Exit menu item will be just like clicking on the Close icon at the top right of the window. This allows for consistency when closing an application in case you ever need to do close processing.
Edit:
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
...
// JMenuItem menuitem8 = new JMenuItem("Exit");
JMenuItem menuitem8 = new JMenuItem( new ExitAction() );