title: Unrecognized selector sent to instance when attempting to call an extension method via a swift bridging header
body: <p>I'm trying to call Objective-C code from Swift. I <a href="https://bohemianpolymorph.wordpress.com/2014/07/11/manually-adding-a-swift-bridging-header/" rel="nofollow">created a Swift Bridging Header</a>, and added an import to the Objective-C file (e.g. <code>#import "UIColor+Utils.h"</code>).</p>
  
  <p>The project builds, and I even get code completion, but when it attempts to execute that line of code, it crashes and says <code>unrecognized selector sent to class</code>.</p>
  
  <p>What did I do wrong?</p>
  
  <p>(Xcode 6.2, iOS 8.2)</p>