title: Why is my object not displaying in JavaFX?
body: <p>This should be a relatively simple problem, but it is driving me insane.  I am trying to create Mine Sweeper in JavaFX (mostly just for practice) but I can not get even a simple rectangle to display.  I had the game running once before, but I am trying to make the game more abstract, and hence easier to code, but I am running into the issue of nothing being displayed.</p>
  
  <p>I eliminated all extraneous code so it is as simple as possible.  I am basically trying to create a Rectangle with a certain color and size called Box, add the box to the pane, and display the pane.  In order to make Box a node that can be displayed on the pane, I made the Box class extend Rectangle, so that a Box would have the same properties as a Rectangle.  But when I run the code, it gives just an empty pane with no box in it.  </p>
  
  <pre><code>import javafx.application.Application;
  import javafx.scene.Scene;
  import javafx.scene.layout.Pane;
  import javafx.stage.Stage;
  
  public class Minesweeper extends Application {
  
      @Override
      public void start(Stage stage) {
  
          Pane pane = new Pane();
  
          Box box = new Box();
  
          pane.getChildren().addAll(box);     
  
          // Create the scene
          Scene scene = new Scene(pane);
          stage.setTitle("Minesweeper");
          stage.setScene(scene);
          stage.show();
  
      }
  
      public static void main(String[] args) {
          launch(args);
      }
  
  }
  
  import javafx.scene.paint.Color;
  import javafx.scene.shape.Rectangle;
  
  public class Box extends Rectangle {
  
      public Box() {
  
          Rectangle box = new Rectangle(100, 100, 100, 100);
  
          box.setFill(Color.BLUE);
  
      }
  
  }
  </code></pre>
  
  <p>I realized if I put the code from Box into the main Minesweeper class, it will display the box.  But Box will have a ton of other properties and therefore needs to be a class on its own.</p>
  
  <p>What am I doing wrong that does not allow the box to be displayed?</p>
  
  <p>Thanks in advance for your help and consideration.</p>