title: Segue and Unwind segue without UI element
body: <p>I have been looking for an answer for this on SO without success.</p>
  
  <p>I have <code>UIViewController</code> A and B. They are NOT linked in Storyboard, and I want to perform a <code>Segue</code> from A to B, and upon clicking a button in B, to activate an <code>unwindSegue</code> to A.</p>
  
  <p>So far I have :</p>
  
  <p>1) The <code>@IBAction</code> in A to unwind back to 
  2) The function to prepare the Segue from A to B (In A)
  3) The button to call the <code>unwindSegue</code> from B to A</p>
  
  <p>What I'm missing is the logic of the function in 2.</p>
  
  <p>More info about B:</p>
  
  <p>Title: FilterView
  Class: FilterViewController
  Storyboard ID: FilterView</p>
  
  <p>I tried creating a segue:</p>
  
  <pre><code>let segueToFilter = UIStoryboardSegue(identifier: "SegueToFilterView", source: self, destination: FilterViewController)
  </code></pre>
  
  <p>Thinking this might just get me what I need.</p>
  
  <p>but I get this error:</p>
  
  <pre><code>Cannot convert value of type 'FilterViewController.Type' to expected argument type UIViewController
  </code></pre>
  
  <p>Help would be appreciated :)</p>