title: swift UIImage blue square
body: <p>I have a project where any image I try to call using .setImage shows a blue square instead of the image.</p>
  
  <pre><code>sender.setImage(UIImage(named: "o.png"), for: [])
  print(sender.tag)
  </code></pre>
  
  <p>any help is greatly appreciated</p>
  
  <p>Edit: I forgot to mention this is setting an image for a button inside of an IBAction </p>