title: How to create a style or theme on swift so I can set color to all UITextField
body: <p>It seems to be pretty obvious but I couldn't find much about it after hours.</p>
  
  <p>I'm build an App on swift 2.0 and I have a dark background to all views.</p>
  
  <p>I want to set a common background and color to all my text views, people recommend that each view should set the properties on viewDidLoad, but I don't want to set to each textView one by one the same information. It will be a hell to maintain.</p>
  
  <p>Any hints?</p>