JavaFX Magic 8 Ball

I was working on a Magic 8 ball written in JavaFX just to try a few things out, and people asked for the code, so here it is. It is nothing special, although I did try to comment the relevant code to make it a bit easier to understand. At around 150 lines of code (including whitespace and comments), it is a very small program, and a good example of what is possible with JavaFX.

To shake the magic 8 ball, you do that - you click on it and shake the ball around. Once you let go the message is updated.

Part of the reason I've posted this is so that people can tell me how to improve my code. If I've done some stupid (likely derived from my life as a Java developer), please let me know.

A screenshot of the program is shown here:


When the ball is shaken, the text and the triangle fade out, and then the triangle fades in with a new message.

A source code download (along with the background image), is available from here. I know I could have coded the ball in JavaFX, but frankly using an image is far easier :-)

Finally, here is the code. Apologies for the need for horizontal scrolling, but it is the best I can do without changing the theme of this site to be wider.

package magic8;

import javafx.stage.Stage;
import javafx.scene.Scene;
import javafx.scene.text.Text;
import javafx.scene.text.Font;
import javafx.scene.image.ImageView;
import javafx.scene.image.Image;
import javafx.scene.shape.Polygon;
import javafx.scene.paint.Color;
import javafx.scene.paint.Stop;
import javafx.scene.paint.LinearGradient;
import javafx.scene.Group;

import javafx.animation.transition.FadeTransition;
import javafx.scene.input.MouseEvent;
import javafx.scene.text.TextAlignment;

import javafx.util.Math;

// the message consists of the triangle and the text
var message: Group;

// the messages to show to the user. We select one randomly each time.
def messages = [
    "Ask Again Later",
    "Better Not Tell You Now",
    "Concentrate and Ask Again",
    "Don't Count on It",
    "It Is Certain",
    "Most Likely",
    "My Reply is No",
    "My Sources Say No",
    "Outlook Good",
    "Outlook Not So Good",
    "Reply Hazy, Try Again",
    "Signs Point to Yes",
    "Yes, Definitely",
    "You May Rely On It"

// the animation when the user shakes the ball. It handles randomly selecting
// the next message
def fadeMessage: FadeTransition = FadeTransition {
    duration: 1s
    node: bind message
    fromValue: 1.0
    toValue: 0.0
    repeatCount: 2
    autoReverse: true
    action: function() {
        // randomly choose one of the messages
        var pos = (Math.random() * sizeof messages) as Integer;
        labelText = messages[pos];

var label: Text;
def wrappingWidth = 80;
var labelText = "Shake the Magic 8 ball";

var imageX: Number;
var imageY: Number;

var isDragged = false;

Stage {
    title: "Magic 8 Ball"
    width: 410
    height: 440
    scene: Scene {
        content: [
            Group {
                translateX: bind imageX;
                translateY: bind imageY;

                content: [
                    // an image of a ball
                    ImageView {
                        image: Image {
                            url: "{__DIR__}magic8ball2.jpg"

                    message = Group {
                        content: [
                            // the triangle inside the magic 8 ball
                            Polygon {
                                points : [ 140,170, 260,170, 200,270 ]
                                fill: LinearGradient {
                                        startX : 0.0
                                        startY : 0.0
                                        endX : 0.0
                                        endY : 1.0
                                        stops: [
                                            Stop {
                                                color : Color.NAVY
                                                offset: 0.0
                                            Stop {
                                                color : Color.BLACK
                                                offset: 1.0

                                stroke: Color.DARKBLUE
                                strokeWidth: 3

                            // the magic 8 ball text
                            label = Text {
                                font : Font { size: 10 }
                                x: 123, y: 190
                                wrappingWidth: wrappingWidth
                                textAlignment: TextAlignment.CENTER;

                                // a bit hacky, but the best way to centre text
                                // when it is short (i.e. 'yes' or 'no')
                                translateX: bind wrappingWidth - (label.boundsInLocal.width)/2
                                content: bind labelText

                onMouseDragged: function(me: MouseEvent) {
                    imageX = me.dragX;
                    imageY = me.dragY;

                    isDragged = true;

                onMouseReleased: function(me: MouseEvent) {
                    if (isDragged) {
                        // run the animation, which handles choosing a new msg
                        isDragged = false;

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