title: Javafx clear stroking rectangle
body: <p>I am new to javaFX and want to try a simple application.<br>
  I have an application with a Canvas and I draw a rectangle, but I can't erase it's border properly.</p>
  
  <p>Here is how I handle it : </p>
  
  <pre><code>Canvas canvas = new Canvas(WIDTH, HEIGHT);
  GraphicsContext g = canvas.getGraphicsContext2D();
  
  g.setFill(colorBackground);
  g.fillRect(0, 0, WIDTH, HEIGHT);
  g.setStroke(Color.BLACK);
  g.strokeRect(200, 200, 10, 10);
  g.setStroke(colorBackground);
  g.strokeRect(200, 200, 10, 10);
  </code></pre>
  
  <p>But I still have a greyish rectangle instead of just nothing. I don't understand why I have this.<br>
  Maybe I use Canvas wrong or something..</p>