title: Swift - viewing different position on viewDidLoad and viewDidAppear
body: <p>I have an understanding problem...
  I created two similar views (same origin and same size) and section view,
  While i created those views - one in <code>viewDidLoad</code> and the other in <code>viewDidAppear</code> - when i put similar starting point in the origin x and y of each view that refer to section i get those views in different position.
  Can someone explain me what is the reason that those views isn't in the same position?</p>
  
  <pre><code>import UIKit
  
  class ViewController: UIViewController {
  
      @IBOutlet var sec: UIView!
  
      override func viewDidLoad() {
          let shape = UIView(frame: CGRect(x: sec.frame.width/2, y: sec.frame.height/2, width: 100, height: 100));
          shape.backgroundColor = UIColor.redColor();
          view.addSubview(shape); 
      }
  
      override func viewDidAppear(animated: Bool) {    
          let shape2 = UIView(frame: CGRect(x: sec.frame.width/2, y: sec.frame.height/2, width: 100, height: 100));
          shape2.backgroundColor = UIColor.greenColor();
          view.addSubview(shape2);
      }
  }
  </code></pre>