Toast.java

import javafx.animation.KeyFrame;
import javafx.animation.KeyValue;
import javafx.animation.Timeline;
import javafx.scene.Scene;
import javafx.scene.layout.StackPane;
import javafx.scene.paint.Color;
import javafx.scene.text.Font;
import javafx.scene.text.Text;
import javafx.stage.Stage;
import javafx.stage.StageStyle;
import javafx.util.Duration;

public final class Toast {
    public static void makeText(Stage ownerStage, String toastMsg, int toastDelay, int fadeInDelay, int fadeOutDelay) {
        Stage toastStage=new Stage();
        toastStage.initOwner(ownerStage);
        toastStage.setResizable(false);
        toastStage.initStyle(StageStyle.TRANSPARENT);

        Text text = new Text(toastMsg);
        text.setFont(Font.font("Verdana", 40));
        text.setFill(Color.RED);

        StackPane root = new StackPane(text);
        root.setStyle("-fx-background-radius: 20; -fx-background-color: rgba(0, 0, 0, 0.2); -fx-padding: 50px;");
        root.setOpacity(0);

        Scene scene = new Scene(root);
        scene.setFill(Color.TRANSPARENT);
        toastStage.setScene(scene);
        toastStage.show();

        Timeline fadeInTimeline = new Timeline();
        KeyFrame fadeInKey1 = new KeyFrame(Duration.millis(fadeInDelay), new KeyValue (toastStage.getScene().getRoot().opacityProperty(), 1)); 
        fadeInTimeline.getKeyFrames().add(fadeInKey1);   
        fadeInTimeline.setOnFinished((ae) -> {
            new Thread(() -> {
                try {
                    Thread.sleep(toastDelay);
                }
                catch (InterruptedException e){
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
                   Timeline fadeOutTimeline = new Timeline();
                    KeyFrame fadeOutKey1 = new KeyFrame(Duration.millis(fadeOutDelay), new KeyValue (toastStage.getScene().getRoot().opacityProperty(), 0)); 
                    fadeOutTimeline.getKeyFrames().add(fadeOutKey1);   
                    fadeOutTimeline.setOnFinished((aeb) -> toastStage.close()); 
                    fadeOutTimeline.play();
            }).start();
        }); 
        fadeInTimeline.play();
    }
}