On my educational trek through the capabilities of JavaFX, I thought it would be a valuable challenge to create Tic Tac Toe. It took me far longer than expected to get this far, but despite likely being even further from completion, I'd like a review on the current state of things and on anything my 'blind coding' unwittingly implemented unconventionally/inefficiently/just plain weirdly.

Some names may seem strange, but that could be due to my editing the image-related code to point to URLs rather than local files for the sake of this post.

TicTacToe main class:

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.image.Image;
import javafx.scene.image.ImageView;
import javafx.scene.layout.GridPane;
import javafx.stage.Stage;
 
public class TicTacToe extends Application {
    static Player player = Player.O_PLAYER;

    public static void main(String[] args) {
        launch(args);
    }

    @Override
    public void start(Stage stage) {
        Button[] cells = new Button[9];
        for (int i = 0; i < cells.length; i++) {
            cells[i] = new Button("",
            new ImageView(new Image("http://i.imgur.com/KAQPbPd.png")));
            registerOnAction(cells[i]);
        }

        GridPane board = new GridPane();
        for (int row = 1, col = 1, cell = 0; row <= 3; row++, col -=2) {
            board.add(cells[cell++], row, col++);
            board.add(cells[cell++], row, col++);
            board.add(cells[cell++], row, col);
        }

        Scene scene = new Scene(board);
        stage.setScene(scene);
        stage.setTitle("TicTacToe By Legato");
        stage.getIcons().add(new Image("http://i.imgur.com/gxhJkc0.png"));
        stage.show();
    }

    private static Image retrieveMarker() {
        player = player == Player.X_PLAYER ? Player.O_PLAYER : Player.X_PLAYER;
        return player.marker();
    }

    private static void registerOnAction(Button button) {
        button.setOnAction(e ->
            button.setGraphic(new ImageView(retrieveMarker()))
        );
    } 
}

Player enum:

import javafx.scene.image.Image;
import javafx.scene.image.ImageView;

public enum Player {
    X_PLAYER(new ImageView(new Image("http://i.imgur.com/HY6GeUY.png"))),
    O_PLAYER(new ImageView(new Image("http://i.imgur.com/KgHHxL6.png")));

    private final ImageView view;

    Player(ImageView view) {
        this.view = view;
    }

    public Image marker() {
        return view.getImage();
    }

    @Override
    public String toString() {
        return name().charAt(0) + name().substring(2).toLowerCase();
    }
}