try {
// Load root layout from fxml file.
FXMLLoader loader = new FXMLLoader();
loader.setLocation(MainQuizCreator.class.getResource("view/RootLayout.fxml"));
rootLayout = (BorderPane) loader.load();
RootLayoutController rootController = loader.getController();
rootController.setMainQuizCreator(this);
// Show the scene containing the root layout.
Scene scene = new Scene(rootLayout, WIDTH, HEIGHT);
primaryStage.setScene(scene);
primaryStage.show();
} catch (IOException e) {