import javafx.animation.KeyFrame;
import javafx.animation.KeyValue;
import javafx.animation.Timeline;
import javafx.application.Application;
import javafx.beans.InvalidationListener;
import javafx.beans.Observable;
import javafx.beans.property.DoubleProperty;
import javafx.beans.property.SimpleDoubleProperty;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.paint.Color;
import javafx.scene.shape.Rectangle;
import javafx.scene.text.Text;
import javafx.scene.text.TextAlignment;
import javafx.stage.Stage;
import javafx.util.Duration;

public class NullTextAlign extends Application {
    public static void main(String argv[]) {
        launch(argv);
    }

    @Override
    public void start(Stage stage) {
        final Rectangle r = new Rectangle(300, 300);
        r.setFill(Color.RED);

        final Text t = new Text("Null test");
        t.setTranslateX(20);
        t.setTranslateY(20);

        final DoubleProperty hue = new SimpleDoubleProperty();
        hue.addListener(new InvalidationListener() {
            public void invalidated(Observable observable) {
                r.setFill(Color.hsb(hue.get(), 1.0, 1.0));
                if (hue.get() > 180) {
                    t.setTextAlignment(null);
                }
            }
        });
        
        stage.setScene(new Scene(new Group(r, t)));
        stage.show();

        KeyValue kv = new KeyValue(hue, 360.0);
        KeyFrame kf = new KeyFrame(Duration.seconds(5), kv);
        Timeline tl = new Timeline(kf);
        tl.setCycleCount(Timeline.INDEFINITE);
        tl.play();
    }
}