Creating a User Interface in JavaFX - JavaFX 8: A Definitive Guide to Building Desktop, Mobile, and Embedded Java Clients - page 58

import javafx.stage.Stage;
import javafx.util.Duration;
public class Metronome1Main extends Application {
DoubleProperty startXVal = new SimpleDoubleProperty(100.0);
Button startButton;
Button pauseButton;
Button resumeButton;
Button stopButton;
Line line;
Timeline anim;
public static void main(String[] args) {
Application.launch(args);
}
@Override
public void start(Stage stage) {
anim = new Timeline(
new KeyFrame(new Duration(0.0), new KeyValue(startXVal, 100.)),
new KeyFrame(new Duration(1000.0), new KeyValue(startXVal, 300., Interpolator.LINEAR))
);
anim.setAutoReverse(true);
anim.setCycleCount(Animation.INDEFINITE);
line = new Line(0, 50, 200, 400);
line.setStrokeWidth(4);
line.setStroke(Color.BLUE);
startButton = new Button("start");
startButton.setOnAction(e -> anim.playFromStart());
pauseButton = new Button("pause");
pauseButton.setOnAction(e -> anim.pause());
resumeButton = new Button("resume");
resumeButton.setOnAction(e -> anim.play());
stopButton = new Button("stop");
stopButton.setOnAction(e -> anim.stop());
HBox commands = new HBox(10,
startButton,
pauseButton,
resumeButton,
stopButton);
commands.setLayoutX(60);
commands.setLayoutY(420);
Group group = new Group(line, commands);
Scene scene = new Scene(group, 400, 500);