import javafx.application.Application;
import javafx.collections.ObservableList;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Insets;
import javafx.geometry.Pos;
import javafx.scene.Node;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.CheckBox;
import javafx.scene.control.Label;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
 
public class StackPaneDemo extends Application {
 
    private StackPane stackPane;
 
    @Override
    public void start(Stage primaryStage) throws Exception {
 
        VBox root = new VBox();
 
        // StackPane
        stackPane = new StackPane();
        
        // add label to StackPane
        Label label = new Label("I'm a Label");
        label.setStyle("-fx-background-color:yellow");
        label.setPadding(new Insets(5,5,5,5));   
        stackPane.getChildren().add(label);
        
        // add Button to StackPane   
        Button button = new Button("I'm a Button");       
        button.setStyle("-fx-background-color: cyan");
        button.setPadding(new Insets(5,5,5,5));
        stackPane.getChildren().add(button);
        
        // add CheckBox to StackPane
        CheckBox checkBox = new CheckBox("I'm a CheckBox");
        checkBox.setOpacity(1);
        checkBox.setStyle("-fx-background-color:olive");
        checkBox.setPadding(new Insets(5,5,5,5));
        stackPane.getChildren().add(checkBox);
        
        stackPane.setPrefSize(300, 150);
        root.getChildren().add(stackPane);
 
        Button controlButton = new Button("Change Top");
 
        root.getChildren().add(controlButton);
        root.setAlignment(Pos.CENTER);
        VBox.setMargin(stackPane, new Insets(10, 10, 10, 10));
        VBox.setMargin(controlButton, new Insets(10, 10, 10, 10));
     
        Scene scene = new Scene(root, 550, 250);
        primaryStage.setTitle("StackPane Layout Demo");
        primaryStage.setScene(scene);
 
        controlButton.setOnAction(new EventHandler<ActionEvent>() {
            @Override
            public void handle(ActionEvent event) {
                changeTop();
            }
        });
 
        primaryStage.show();
    }
 
    private void changeTop() {
        ObservableList children = this.stackPane.getChildren();
 
        if (children.size() > 1) {
            //
            Node topNode = (Node) (children.get(children.size()-1));
            topNode.toBack();
        }
    }
 
    public static void main(String[] args) {
        launch(args);
    }
 
}