Accessing FXML controller class

Question

I would like to communicate with a FXML controller class at any time, to update information on the screen from the main application or other stages.

Is this possible

Answer 1

On the object's loading from the Main screen, one way to pass data that I have found and works is to use lookup and then set the data inside an invisible label that I can retrieve later from the controller class. Like this:

Parent root = FXMLLoader.load(me.getClass().getResource("Form.fxml"));
Label lblData = (Label) root.lookup("#lblData");
if (lblData!=null) lblData.setText(strData); 

This works, but there must be a better way.