title: Using javafx using circle.setCenterX and circle.setCenterY not working
body: <p>I am working through some coursework and am running into an odd issue. I'm working with javafx learning how to build shapes and work with alignment. Anyway my circle object will not respond to setCenterX or setCenterY commands (the radius definition statement does work) in the original definition statements nor in the commands issued by my event handlers which should be redefining these set x and set y values.  I cannot figure out why. Please see my code below. When working correctly my code would allow me to move the circle object around the screen with the buttons and event handlers I've created. If I can figure out why the setCenterX and setCenterY don't work, I'm sure I can get the rest. Thanks for your help in advance.</p>
  
  <pre><code>package bravo15;
  
  import javafx.application.Application;
  import javafx.geometry.Pos;
  import javafx.scene.Scene;
  import javafx.scene.control.Button;
  import javafx.scene.layout.HBox;
  import javafx.scene.layout.Pane;
  import javafx.scene.paint.Color;
  import javafx.scene.shape.Circle;
  import javafx.scene.layout.BorderPane;
  import javafx.stage.Stage;
  import javafx.scene.Scene;
  
  
  public class FifteenDotThreeVersionThree extends Application {
  
  
  @Override // Override the start method in the Application class
  public void start(Stage primaryStage) {
  
  Circle circle = new Circle();
  circle.setCenterX(300);
  circle.setCenterY(300);
  circle.setRadius(50);
  
  // Hold four buttons in an HBox
  // Define hbox
  HBox hBox = new HBox();
  hBox.setSpacing(10);
  hBox.setAlignment(Pos.CENTER);
  
  // define buttons
  Button btLeft = new Button("Left");
  Button btRight = new Button("Right");
  Button btUp = new Button("Up");
  Button btDown = new Button("Down");
  
  // add defined buttons into the hbox
  hBox.getChildren().add(btLeft);
  hBox.getChildren().add(btRight);
  hBox.getChildren().add(btUp);
  hBox.getChildren().add(btDown);
  
  // Create and register the handlers for the four buttons
  btLeft.setOnAction(e -&gt; circle.setCenterX(circle.getCenterX() - 10));
  btRight.setOnAction(e -&gt; circle.setCenterX(circle.getCenterX() + 10));
  btUp.setOnAction(e -&gt; circle.setCenterY(circle.getCenterY() + 10));
  btDown.setOnAction(e -&gt; circle.setCenterY(circle.getCenterY() - 10));
  
  
  BorderPane borderPane = new BorderPane();
  borderPane.setTop(circle);
  borderPane.setBottom(hBox);
  BorderPane.setAlignment(hBox, Pos.CENTER);
  
  
  // Create a scene and place it in the stage
  Scene scene = new Scene(borderPane, 200, 200);
  primaryStage.setTitle("ControlCircle Version 3"); // Set the stage title
  primaryStage.setScene(scene); // Place the scene in the stage
  primaryStage.show(); // Display the stage
  
  }
  
  /**
  * The main method is only needed for the IDE with limited
  * JavaFX support. Not needed for running from the command line.
  */
  public static void main(String[] args) {
    launch(args);
  }
  }
  </code></pre>