title: How to use animationDidStop in swift
body: <p>I am new to Swift.
  Say I have an array of UIImage loaded with image1 to image4. Assign to a UIImageView.
  I set the animation to repeat only once. Once the animation stop playing I would like a function to be called, preferably able to attach parameters when calling.</p>
  
  <p>How can this be done? My research only let me know I may have to do
  override func animationDidStop</p>
  
  <p>If I have more than one set of animation happening at the same time, how do I know which set of animation is calling?</p>
  
  <p>Thanks in advance
  sweekim</p>