showDialogNamedDie

  private void showDialogNumbered() {
    /*// Create the custom dialog.
    Dialog<Pair<String, String>> dialog = new Dialog<>();
    dialog.setTitle("Create a numbered die");
    dialog.setHeaderText(null);
    // Set the button types.
    ButtonType saveButtonType = new ButtonType("Save", ButtonBar.ButtonData.OK_DONE);
    dialog.getDialogPane().getButtonTypes().addAll(saveButtonType, ButtonType.CANCEL);

    // Create the name and sides labels and fields.
    GridPane grid = new GridPane();
    grid.setHgap(10);
    grid.setVgap(10);
    grid.setPadding(new Insets(20, 150, 10, 10));

    TextField name = new TextField();
    name.setPromptText("Name");
    TextField sides = new TextField();
    sides.setPromptText("Sides");

    grid.add(new Label("Name:"), 0, 0);
    grid.add(name, 1, 0);
    grid.add(new Label("Sides:"), 0, 1);
    grid.add(sides, 1, 1);

    dialog.getDialogPane().setContent(grid);

// Request focus on the name field by default.
    Platform.runLater(name::requestFocus);

// Convert the result to a name-password-pair when the login button is clicked.
    dialog.setResultConverter(dialogButton -> {
      if (dialogButton == saveButtonType) {
        return new Pair<>(name.getText(), sides.getText());
      }
      return null;
    });

    Optional<Pair<String, String>> result = dialog.showAndWait();

    result.ifPresent(usernamePassword -> {
      System.out.println("Username=" + usernamePassword.getKey() + ", Password=" + usernamePassword.getValue());
    });*/
    Alert dialog = new Alert(Alert.AlertType.CONFIRMATION);
    dialog.setTitle("Create a new numbered die");
    dialog.setHeaderText(null);

    ButtonType buttonTypeSave = new ButtonType("Save");

    dialog.getButtonTypes().setAll(buttonTypeSave,ButtonType.CANCEL);

    // Create the name and sides labels and fields.
    GridPane grid = new GridPane();
    grid.setHgap(10);
    grid.setVgap(10);
    grid.setPadding(new Insets(20, 150, 10, 10));

    TextField name = new TextField();
    name.setPromptText("Name");
    TextField sides = new TextField();
    sides.setPromptText("Sides");
    CheckBox isDecreasing = new CheckBox();

    grid.add(new Label("Name:"), 0, 0);
    grid.add(name, 1, 0);
    grid.add(new Label("Sides:"), 0, 1);
    grid.add(sides, 1, 1);
    grid.add(new Label("Is Decreasing?"), 0, 2);
    grid.add(isDecreasing, 1, 2);

    dialog.getDialogPane().setContent(grid);

    Optional<ButtonType> result = dialog.showAndWait();
    if (result.get() == buttonTypeSave) {
      // ... user chose OK
      try {
        if (isDecreasing.isSelected()) {
          dicingService.saveNumberedDecreasingDie(name.getText(), Integer.parseInt(sides.getText()));
        } else {
          dicingService.saveNumberedDie(name.getText(), Integer.parseInt(sides.getText()));
        }
      } catch (IllegalParameterException
          | NameAlreadyUsedException e) {
        showAlert(e.getMessage());
      } catch (NumberFormatException e){
        showAlert("Please enter a whole number in field 'sides'");
      }
      dieNameBox.getItems().add(name.getText());
    }
  }