JavaFX Stage显示空的场景

Question

I've been trying to open a new Window in order to display a progress bar, from a controller :

    Stage fenetre = new Stage();
    fenetre.initModality(Modality.APPLICATION_MODAL);

    FXMLLoader loader;
    Parent root;
    Scene chargementBox;

    loader = new FXMLLoader();
    loader.setLocation(getClass().getResource("/views/Chargement.fxml"));
    loader.load();
    root = loader.getRoot();
    chargementBox = new Scene(root);

    fenetre.setTitle("Chargement");
    fenetre.resizableProperty().set(false);    
    fenetre.setScene(chargementBox);
    fenetre.show();

It shows the window. But it's empty :

This is what it should show

This is what i got instead

I tried everything, I used other FXML files, the window sizes are correct but it's always empty. The same code works on other Controllers, but not here.

Help please. There is no exceptions and no errors. Thank's

---

Edit : I've found the reason why it doesn't show, it's because later in the code i have this function : Transport.send(message); that blocks the program from refreshing my scene and displaying the elements. Is there a way i can run that line in the background or in another thread (I never used threads before.) Thank's again for the help.

Answer 1

To run something on the background thread you need to either use a task (useable once) or a service (reusable).

This is how you can use a service:

Service<Void> service = new Service<Void>(){
            @Override
            protected Task<Void> createTask() {
                return new Task<Void>() {
                    @Override
                    protected Void call() throws Exception {
                            //do your logic here.
                        return null;
                    }
                };
            }
        };
        service.setOnSucceeded(event -> {
                //do some processing when complete
             });
        service.setOnFailed(event -> {
               //do some processing when it failes
             });

        service.start();