JavaFX StackPane add Button

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.StackPane;
import javafx.stage.Stage;

public class Main extends Application {
  @Override//from ww  w  . j  a v  a  2s . c om
  public void start(Stage primaryStage) {
    // Create a scene and place a button in the scene
    StackPane pane = new StackPane();
    pane.getChildren().add(new Button("OK"));    
    Scene scene = new Scene(pane, 200, 50);
    primaryStage.setTitle("Button in a pane");
    primaryStage.setScene(scene);
    primaryStage.show();
  }
  

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