title: JavaFX - How can I fill with color a shape?
body: <p>Let's say that I have an application window and I declare <code>Circle c = new Circle(40,40,40);</code>, which is initially black. What should I do if I want to fill it with red? </p>
  
  <p>What should I do if I want to fill it with red? (for example, if a button is clicked, then <code>c</code> becomes red)</p>