How to return value from a stage before closing it?

Question

First of all, sorry for the bad english.

Here is the case:

I have a \"main stage\" where i press a button to open a \"second stage\" where i have a table, th

Answer 1

In my main controller I create Stage. Load controller which I can use like any class. And by creating an event I can get data just before closing the window.

try {
        FXMLLoader loader = new FXMLLoader();
        loader.setLocation(getClass().getResource("/package/mySceneBuilderWindow.fxml"));
        final Pane rootPane = (Pane)loader.load();
        Scene scene =  new Scene(rootPane);

        Stage stage = new Stage();
        stage.setTitle("Optional title");
        stage.setScene(scene);

        mySceneBuilderWindowController controller = loader.getController();
        controller.iCanSendDataToCtrl("String for now"); // sending data or init textFields...

        stage.show();

        /* set event which is fired on close
            // How to close in the other window... (pressing X is OK too)
                @FXML private Button fxidSave = new Button(); // global var
                @FXML private void handleSaveButton() {
                    Stage stage = (Stage) fxidSave.getScene().getWindow();
                    stage.close(); // closes window
                }
         */
        stage.setOnCloseRequest((EventHandler) new EventHandler() {
            public void handle(WindowEvent we) {
                String iCanGetDataBeforeClose = controller.getData();
                System.out.println(iCanGetDataBeforeClose);
                // static class can be used aswell -> System.out.println(Context.getMyString());
            }
        });

    } catch (IOException e) {
        System.out.println("something wrong with .fxml - name wrong? path wrong? building error?");
    }  

My other mySceneBuilderWindowController methods:

 public void iCanSendDataToCtrl(String giveMe) {
    // do something ex. myTextBox.setText(giveMe);
 }
 public String iCanGetDataBeforeClose() {
    // do something ex. return myTextBox.getText();
 }