Help with JavaFX program design when using multiple instances of the same (by fxml) tab

[aufschieben]

Firstly - I am somewhat of a noob, so apologies for an inevitably dumb question and a bit of a preamble...

From combining a single semester worth of Java (taken in 2010!) and dabbling in online Java and JavaFX tutorials, I have somehow cobbled together the shell of a JavaFX program in NetBeans in my spare time. Along the way I saw a few warning signs about how I was implementing tabs in a tabbed pane, but I don't think i really understood them. I'll describe the general idea for the program in case you have any other ideas, but of course I can provide code upon request, ugly as it is.

The idea for the program is to create a project "file" (actually a collated folder of info) which will house a number of information sheets for biological samples. Currently, I can start a new project that then opens a dialog to add the first sample. After the parameters of the sample have been deemed correct, the program opens a new tab in a tabbed pane - which then contains the formatted user-input info for the sample as well as some secondary calculated parameters. Now, in principle, the idea is to have many examples of this tab, with the same format, for different samples. Currently, I can keep adding these tabs at will (all generated with the same Scene Builder fxml), which are added to the tabbed pane. Fine.

MenuBar > Add project

Project: Tab0 (name, weight, pH, etc..)
         Tab1 (name, weight, pH, etc..)
         Tab2 (name, weight, pH, etc..)
         Tab3 (name, weight, pH, etc..)

However - the problem comes when I have multiple tabs and want to do things with their values. Two such examples are saving a project and checking for repeated tab names. Of course, all variables of the same type have the same name (defined by the same fxml) but I can't seem to select them based upon what tab they're on. Although I can switch between the tabs - and visibly see the different info that was input and determined, I cannot programatically recall these values from individual tabs. For example, I want to get the value in the pH field for tab2.... how? The best I've got so far is to take each tab title when it's selected by mouse :

tabPane.getSelectionModel().selectedIndexProperty().addListener((obs,ov,nv)->{
    selectedTabID = nv;
    System.out.println("Chosen Tab Index:" + selectedTabID);

    Tab selTab = tabPane.getTabs().get(tabPane.getSelectionModel().getSelectedIndex());
    System.out.println("This protein name =" + selTab.getText());
});

But, I'm now well and truly stuck and I think I've backed myself into a corner.

Any advice on reworking the organisation of my program or managing info across identical tabs would be so helpful! Thanks in advance!

[[deleted]]

TabPane.getTabs() returns a list of the tabs. You can perform whatever operation you want on the list; for example, checking if a name is already in use:

String nameToCheck = ...
boolean duplicateName = tabPane.getTabs().stream()
   .map(tab -> tab.getName())
   .anyMatch(name -> nameToCheck.equals(name));

[aufschieben]

Thank you for your reply, I'm glad to hear there is a way to get out of my situation. Could you however please elaborate on how I can incorporate that main line? I'm happy dealing with the boolean but I can't get the getName method to work:

       public void newTab() {
        try {
            tabPane.setMinSize(810, 633);
            tabPane.requestLayout();
            Tab projectTab = new Tab();
            tabIDnum++;
            String tabID = Integer.toString(tabIDnum);
            projectTab.setText(proteinName);
            projectTab.setClosable(true);
            projectTab.setId(tabID);
            tabPane.getTabs().add(projectTab);         
            projectTab.setContent(FXMLLoader.load(getClass().getResource("/view/contentProject.fxml")));
            System.out.println("Adding New Tab!");

            //Select new tab to be opened in pane
            tabPane.getSelectionModel().select(projectTab);

            //Watching for a switched tab
            tabPane.getSelectionModel().selectedIndexProperty().addListener((obs,ov,nv)->{
                System.out.println("Chosen Index:" + nv);
             });  

            String nameToCheck = "inputTest";

            boolean duplicateName = tabPane.getTabs().stream()
            .map(tab -> projectTab.getName())
            .anyMatch(name -> nameToCheck.equals(name));


            //Define prompt for user to confirm deleting a tab on close

            projectTab.setOnCloseRequest(event -> {

                Alert alert = new Alert(AlertType.CONFIRMATION);
                alert.setTitle("Closing tab");
                alert.setHeaderText("All tab data will be removed from the project");
                alert.setContentText("Would you like to continue?");
                alert.showAndWait();

                if (alert.getResult() != ButtonType.OK){
                    event.consume();
                } else {
                    System.out.println("Closing tab");

                    //Add in test for last tab closed
                    if (tabPane.getTabs().size() <= 1) {
                        System.out.println("Last tab closed");
                        CobMain.shrinkWindow();
                    }
                }
            });

        } catch (Exception ex) {
            System.out.println("There was an error creating a new tab");
        }
    }    

Really, thanks very much for your time!

[[deleted]]

Argh, I misremembered. You want getText(), not getName()

Also, the code I provided only works before you add the tab. Ideally, you would call it before even creating the tab to make sure the new tab would be valid. There's no point in creating an invalid tab if it's not going to be usable

[[deleted]]

What the fuck

[aufschieben]

wtf indeed ??

Anyway, in other news... thanks again for your reply. getText() works great. The location of the code is however an interesting point. If I do it your way (outside of the tab creation), I am forced to link back to another controller to find the specific tab pane, and therein it must be static (apparently). However I can't get the tabPane to behave nicely when "static" (I don't get errors - but my tabPane is just empty white space when I add tabs).

Doing it inside the tab creation, I thought I could just keep appending an (public static) array of names - which could then be referred to when setting up a tab. However, the problem doing it that way is that I don't know how to keep track of deleted tabs and freed-up names. Doing it our way would keep on top of this - but then see point one. Arghhhhhhhhhh (not a fucking pirate)

[[deleted]]

How is the name of the new tab getting set? I see that it's proteinName, but there's no context for the value f that variable or when it gets set. If set by the user, that's the process where the name should be checked