title: VC's Element not accessible from applicationWillResignActive
body: <p>I have </p>
  
  <p><code>var vc = MenuVC()</code> in <code>AppDelegate</code></p>
  
  <p>and inside </p>
  
  <p><code>applicationWillResignActive</code> I have: <code>vc.waitCancelButtonTapped(self)</code></p>
  
  <p>Then inside </p>
  
  <p><code>MenuVC()</code> method <code>waitCancelButtonTapped</code> </p>
  
  <p>I have a bunch of code which all works good but when it comes to </p>
  
  <p><code>spinner.stopAnimating()</code> or <code>waitView.hidden = true</code> </p>
  
  <p>it crashes with error. </p>
  
  <blockquote>
    <p>fatal error: unexpectedly found nil while unwrapping an Optional value</p>
  </blockquote>
  
  <p>What am I missing?</p>