JavaFX - parsing child arguments back to parent - button

Question

I have 2 Controllers and I want to pass values from second controller to first controller, here are code sample:
FXMLController.java
private int paramAnswers;
private int paramNotificationTime;
private int paramNotificationDelay;
#FXML
private void handleMenuItemOptionsAction(ActionEvent event) throws IOException{
Parent root = FXMLLoader.load(getClass().getResource("/fxml/Options.fxml")); // UNDECORATED*
Scene scene = new Scene(root, Color.TRANSPARENT);
final Stage stage = new Stage();
stage.setTitle("Options");
stage.setScene(scene);
stage.show();
}
public void setOptionsParams(int paramAnswers, int paramNotificationTime, int paramNotificationDelay){
this.paramAnswers = paramAnswers;
this.paramNotificationTime = paramNotificationTime;
this.paramNotificationDelay = paramNotificationDelay;
}
and second controller:
OptionsController.java
private FXMLController parentController;
private int paramAnswers;
private int paramNotificationTime;
private int paramNotificationDelay;
#Override
public void initialize(URL location, ResourceBundle resources) {
.... }
#FXML
private void handleButtonSaveAction(ActionEvent event) throws IOException{
/*Pass these parameteres OptionsController parameters back to the FXMLController like parentController.setOptionsParams(paramAnswers, paramNotificationTime, paramNotificationDelay);
*/
(((Button)event.getSource()).getScene().getWindow())).close();
}
Arleady tried with parsing FXMLControler as .this into OptionsController initialize method, tried making listers and bunch of other resolved problems on stackoverflow but it just don't want work :< I need to pass that atributes back to FXMLController and close child window, so my main app would change behavior depending on passed values... :X
For any help I will be grateful

Answer 1

you can have a function in the second controller let's say passParams() set it's parameters what every you want to pass to that controller and from the first controller when you click on a button or something
this line
FXMLLoader.load(getClass().getResource("/fxml/Options.fxml"));
need to be changed to
FXMLLoader loader = new FXMLLoader(getClass().getResource("/fxml/Options.fxml"));
Parent root = (Parent) loader.load();
OptionsController controller = loader.getController();
EDIT
you need to pass the first controller to the second controller
controller.setParentController(this); // this is the first controller
in Second controller
FirstController mController;
public void setParams(FirstController controller) {
this.mController = controller;
}
now in the button click function you use the mController you got from the previous step
mController.setOptionsParams(...); //send the params collected from the textfields
this function is implemented in the FirstController
Note: a more general way to do this by using call-backs it's the same but your code depends on interfaces not concrete classes by implementing a general interface in FirstController that have the setOptionParams() method

Answer 2

First you add a callback interface to your parent controller class:
public interface OptionCallback {
public void setOptionsParams(int paramAnswers, int paramNotificationTime, int paramNotificationDelay);
}
public class YourParentController implements Initializable, OptionCallback {
...
}
Using the FXMLLoader object you can get a hold of your child controller object and pass the parent object to it:
FXMLLoader loader = new FXMLLoader(getClass().getClassLoader().getResource("yourFXML.fxml"));
Parent root = (Parent) loader.load();
YourChildController yourChildController = loader.<YourChildController>getController();
yourChildConrtoller.registerCallback(this);
In the childController you save that callback:
private OptionCallback optionCallback;
public void registerCallback(OptionCallback callback) {
optionCallback = callback;
}
And whenever results are ready you use it to pass it to parent:
optionCallback.setOptionsParams(...);