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Toggling Menu Items in JavaFX

I have created a class which extends JavaFX's MenuBar that creates a menu bar for my application.
By default I won't specialized operations, like opening/saving a file and running a simulation, to be disabled (and they are). When a user runs the app they can select an item in the menu File>New>, and based on which component they select it will toggle on the appropriate menu options.
I was planning on doing this by having each component give a list of which items it toggles on, and then activating the appropriate items when the component is created.
However, I cannot access the list of menus from within in a function (am trying to do it with this.getMenus() but from within the function the only function that is recognized it this.getClass()).
Does anyone know why I cannot call getMenus() and how I could get access to it?
Alternatively, if you have a better idea for how I can toggle these menu items, I'd love to hear. I don't think this is a good way to do it, but it is the best idea we have come up with.
private void fileNew()
{
Menu fileNew = new Menu("New");
menuFile.getItems().add(fileNew);
for(String k: CLHM.keySet())
{
CComponent comp = CLHM.get(k);
if(comp.supportedFeatures().contains((new SupportsNew())))
{
MenuItem i = new MenuItem(comp.getName());
fileNew.getItems().add(i);
i.setOnAction(new EventHandler<ActionEvent>()
{
#Override
public void handle(ActionEvent event)
{
CComponent ctemp = CLHM.get(i.getText());
ArrayList<String> menuItems = (ArrayList) ctemp.getMenuItems();
for (String s : menuItems)
{
Scanner scanner = new Scanner(s).useDelimiter("\\s>\\s");
String menu = scanner.next();
//Menu temp = this.getMenus();
/*
Here the program will parse the string of the
Menu path (e.g. File>Open) and activate the
relevant item, if it exists.
*/
}
borderPane.setCenter((Node) ctemp);
}
});
}
}
}

When you use this inside an anonymous class, it actually refers to the anonymous class instance. So in your case, this is an instance of EventHandler, which is why there are so little methods that you can call (because it is an interface type).
What you are looking for is YourExtendedMenuBar.this.getMenus(). This will tell the compiler that you are looking for the enclosing instance. Alternatively, you can simply drop the this keyword (i.e. getMenus()). Doing so will allow you to use/call any accessible members of the anonymous class and its enclosing class.
On the side note, if you replaced that anonymous class with a lambda expression, then this would have meant YourExtendedMenuBar. It is not possible to access any members of the class that the lambda expression represents, at least not directly.
P.S. I have no idea what your toggling is all about, so I can't answer until I figured out what you mean.

JComboBox get item

I have a quick question. I don't get it...
I've got a JFrame where I add a JComboBox:
JComboBox<String> Team_ComboBox = new JComboBox<>();
Team_ComboBox_Handler ComboBox_Listener = new Team_ComboBox_Handler();
Team_ComboBox.addActionListener(ComboBox_Listener);
Team_ComboBox.addItem("Test 1");
Team_ComboBox.addItem("Test 2");
On this Frame I have a button which opens another JFrame.
Play = new JButton();
Play.setText("Play");
Play.setPreferredSize(dimension);
Play.addActionListener(menuhandler);
private class main_menuhandler implements ActionListener {
#Override
public void actionPerformed(ActionEvent e) {
if(e.getSource()==Play){
teams Team = new teams();
Team.teams();
disposeMainMenue();
}
if(e.getSource()==Close) {
System.exit(DO_NOTHING_ON_CLOSE);
}
}
}
Anyway, I would like to transfer the Selected value of the Combobox to a method of the other class. I know how I can get the itemvalue of the combobox in the method itself (with getselecteditem) But how can I do that in the ActionPerformed Method as I can't access the combobox in the ActionPerformed method.... I created another ActionListener (comboBox_Listener) but I haven't put any code into it...
Any idea? Thanks a lot in advance

Several issues appear to me:
Your main question:
But how can I do that in the ActionPerformed Method as I can't access the combobox in the ActionPerformed method
Your likely best solution is to change your code and variable declaration placement so that you can access the JComboBox fromt he actionPerformed method. If you're declaring the combobox from within a method or constructor, change this so that it is a proper instance field of the class.
Other problems:
You should not be creating multiple JFrames. If you need a dependent window, then one should be a JDialog. If not, then consider swapping views with a CardLayout.
Learn and follow Java naming conventnions so others can better understand your code. Class names begin with capital letters and methods and variable names don't for instance.
I am not sure why you're doing this: System.exit(DO_NOTHING_ON_CLOSE);. Why pass that constant into the exit method?

Use a constructor for your action listener class:
private class main_menuhandler implements ActionListener {
private JComboBox<String> Team_ComboBox;
public main_menuhandler(JComboBox<String> Team_ComboBox){
this.Team_ComboBox = Team_ComboBox;
}
}
Now you can create the class main_menuhandlervia the constructor and add the combobox to it.
In your Overriden action you have access to it.
Try playing around with this as your code snippet isn't broad enough to actually provide proper code. But this should answer your question

Adding attributes to jButton [JAVA]

Lets say i have an array of 100 employees. Each employee in the array, is an instance of the class Employee, that have many attributes, such as name, direction, salary, etc.
I want to display, 1 button for each employee in the array, and when you click one, you get the information of that employee.
What i don't know, is how can i link a button to an specific employee. I Was thinking on, somehow, attaching an Integer variable to the button, so i know which employee is related to that specific button, but, i don't really know how to do that.
Anyone cares to give me some advice on this?

You could use setName(employeeId) method for JButton to set Employee's id or use putClientProperty("id", employeeId), when you get a callback at button's listener you could get the name or your property.

You can use the putClientProperty and getClientProperty to attach any object to a JComponent.

If you get "this" inside listener you get a reference to listener's object. You should use getSource() method, like:
JButton j = new JButton("click here");
j.putClientProperty("id", "employee1");
j.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent ae) {
JButton source = (JButton)ae.getSource();
String id = (String) source.getClientProperty("id");
System.out.print(id);
}
});
Will print - employee1.

How do I access the source of an ActionEvent when the ActionListener is located in a different class?

I can't get my head round this one. I've tried to adhere to the MVC pattern for the first time and now have difficulties accessing the source of an ActionEvent because the ActionListener is located in a different class. But let the code do the talking...
In the "view":
// ControlForms.java
...
private JPanel createSearchPanel() throws SQLException {
...
comboBoxCode = new JComboBox(); // Field comboBoxCode -> JComboBox()
SwingUtilities.invokeLater(new Runnable() {
public void run() {
AutoCompleteSupport<Object> support = AutoCompleteSupport.install(
comboBoxCode, GlazedLists.eventListOf(jnlCodeArray));
}
}); // Auto-Complete comboBox from GlazedLists
...
public void setComboListener(ComboListener comboListener) {
comboBoxCode.addActionListener(comboListener);
}
...
}
Then, in what I term the controller, I have two different classes:
// Controller.java
public MyController() throws SQLException {
...
addListeners();
}
...
private void addListeners(){
View view = getView();
getView().getControlForm().setComboListener(new ComboListener());
}
and
public class ComboListener implements ActionListener {
public void actionPerformed(ActionEvent e) {
System.out.println("ComboBox listened to! e = " + e.toString());
}
}
Now, e obviously doesn't give the name of the variable (which at the moment I wish it would), so I cannot if test for e.getSource().
My question is thus: is there either a) a way to query (via if for example) the source of e, or b) a less complicated way to get to the variable name?
Many, many thanks in advance for your insights and tips!

Why do you need the name of the variable? Why can't you do the event handling like this
public class ComboListener implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
JComboBox source = (JComboBox)e.getSource();
//do processing here
}
}
I'd think that if you need to do processing according the variable name, obviously you need different listeners for different combo boxes.

Generally, there are only two situations in which you should use a listener like that: a) you're going to handle a certain event the same way for a bunch of objects, or b) you're only going to use the listener for one object. In the latter case, I'd prefer handling the event locally anyway.
That said, the direct answer to your question is: you shouldn't have to check inside your ActionListener implementation to see whether the appropriate object is the source of the event; you should simply only add the ActionListener to that one object.
One final note: without knowing the specifics of your architecture... generally, MVC will treat all event handling as part of the View (it reduces coupling) and the View will pass commands or method calls or your own events (i.e., not Swing's) to the Controller.

Regarding Multiple Tab-Class

I've problem regarding GUI with one Menu and one Order Class.
I've created a variable to store how many items have been selected in the Menu Class.
private int totalSelected;
The var totalSelected is live updated. It can be changed anytime depending on actionPerformed() function.(Exp: totalSelected will add up all the selected items)
In the Order Class, how can I access to the live update variable totalSelected in order to retrieve the live update value? When I invoke getTotalSelected() function inside the Menu Class, I will only obtain a 0 value.
Thanks for your help ^^!
Please allow me to specify my question clearer.
public class MenuTab extends JPanel
{
private JLabel display;
private int totalSelected;
public MenuTab()
{
....
}
}
public getTotalSelected(){
return totalSelected;
}
private class SelectedListener implements ActionListener
{
public void actionPerformed()
{
.......
//Assume that totalSelected has been updated!
display = new JLabel("Total: " + totalSelected);
// OK to display totalSelected live value here.
}
}
// A new class is the confirmation of order
public class OrderConfirmedTab extends JPanel{
private JLabel displayTotal;
private MenuTab order = new MenuTab();
public OrderConfirmedTab()
{
......
int totalSelected = order.getTotalSelected();
displayTotal = new JLabel("Total: " + totalSelected);
// Problem to display totalSelected live value here.
// Will obtain 0;
// How can I obtain the live updated value from class MenuTab? Thanks!
}
}

If I read your code right, you need to make your variable be private static int totalSelected; You need to make it static so that it stays the same for all instances of the class.

I looks like your not updating the private int totalSelected; variable when a user makes a selection, so it is always 0.

Ya! I just realized that my JLabel
will not update the value
automatically. So how can I fix it?
Thanks! – Christine
If I understand you correctly you have two GUIs where changes in one (the MenuTab) will update the other (OrderConfirmedTab) in real time?
If so, you will need to increase the coupling between the two objects. If MenuTab has a reference back to OrderConfirmedTab then it can call methods to update the value as it changes.
For example, pass OrderConfirmedTab into MenuTabs constructor
MenuTab mt = new MenuTab(this); // from within OrderConfirmTabs costructor
Then when MenuTab has an actionPerformed event it can call back to OrderConfirmTab
orderConfirmTab.setTotalSelected(totalSelected); // you have to create this method in OrderConfirmTab
I hope this helps a little

You can use PropertyChangeListener and PropertyChangeSupport mechanisms to dispatch an event when the value is updated and to be notified when the variable has changed. Your JLabel is not going to update on its own; even if you were to use an object other than a primitive (note that primitives are merely values, while objects are actually implicit pointers); you will need to update your JLabel when the variable changes, since the JLabel simply stores a string, not a reference to the variables from which the string was constructed.
This is the concept of model-view-controller; your variable should be in some sort of class or classes that represent the model (the information) and which allow changes to be observed via property change events. Your view classes should simply provide display logic and no business or application-specific logic. It is the controller in which your application logic should reside; your controller should register for events on the model, and it should update the view whenever the model has changed, and it should likewise update the model when the view dispatches events that should result in the model being changed.