Invalidation Listeners

Invalidation listeners tem um método simples que você subscreve com expressões lambda. Vamos utilizar sem o método lambda. Quando você clicar no StackPane, o clique do mouse vai rotacionar o StackPane.

O segundo objeto Text irá mostrar o status da animação da RotationTransition, que apenas manipula a propriedade de status de leitura. Você verá RUNNING, PAUSED ou STOPPED.

O código ficará assim:

package sample;

import javafx.animation.Animation;
import javafx.animation.Interpolator;
import javafx.animation.RotateTransition;
import javafx.application.Application;
import javafx.beans.InvalidationListener;
import javafx.beans.Observable;
import javafx.beans.value.ObservableObjectValue;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.effect.Reflection;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.VBox;
import javafx.scene.paint.Color;
import javafx.scene.shape.Ellipse;
import javafx.scene.text.Font;
import javafx.scene.text.Text;
import javafx.stage.Stage;
import javafx.util.Duration;

public class Main extends Application {

    @Override
    public void start(Stage stage) throws Exception {
        Ellipse ellipse = new Ellipse(110, 70);
        ellipse.setFill(Color.LIGHTBLUE);
        Text text = new Text("Minhas Formas");
        text.setFont(new Font("Arial Bold", 24));

        Reflection r = new Reflection();
        r.setFraction(.8);
        r.setTopOffset(1.0);
        text.setEffect(r);

        StackPane stackPane = new StackPane();

        // Define RotateTransition
        RotateTransition rotate = new RotateTransition(
                Duration.millis(2500), stackPane);
        rotate.setToAngle(360);
        rotate.setFromAngle(0);
        rotate.setInterpolator(Interpolator.LINEAR);
        // configure mouse click handler
        stackPane.setOnMouseClicked(mouseEvent -> {
            if (rotate.getStatus().equals(Animation.Status.RUNNING)) {
                rotate.pause();
            } else {
                rotate.play();
            }
        });

        stackPane.getChildren().addAll(ellipse, text);


        Text text2 = new Text("");
        text2.setFont(new Font("Arial Bold", 24));

        rotate.statusProperty().addListener(new InvalidationListener() {
            @Override
            public void invalidated(Observable observable) {
                text2.setText("Animation status: " +
                        ((ObservableObjectValue<Animation.Status>)observable)
                                .getValue());
            }
        });

        VBox vBox = new VBox();
        vBox.setAlignment(Pos.CENTER);
        vBox.getChildren().addAll(stackPane, text2);

        Scene scene = new Scene(vBox, 350, 330, Color.LIGHTYELLOW);
        stage.setTitle("Minhas Formas com JavaFX");
        stage.setScene(scene);
        stage.show();
    }


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