@FXML
private void handleButtonAction(ActionEvent event) {
System.out.println("You clicked me!");
label.setText("Hello World!");
//Here I want to swap the screen!
Stage stageTheEventSourceNodeBelongs = (Stage) ((Node)event.getSource()).getScene().getWindow();
// OR
Stage stageTheLabelBelongs = (Stage) label.getScene().getWindow();
// these two of them return the same stage
// Swap screen
stage.setScene(new Scene(new Pane()));
}