title: How to make UICollectionView custom layout?
body: <p>I want to make such as custom CollectionView layout.
  <a href="https://i.stack.imgur.com/YfYu1.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/YfYu1.jpg" alt="enter image description here"></a></p>
  
  <p>Each cell's location will be random but cells should not be overlapping each other. 
  I have tried <a href="https://github.com/DoddaSrinivasan/DSCircularCollectionView" rel="nofollow noreferrer">DSCircularCollectionView</a> but I want cell position randomly without overlapping. How can I make it with Objective-c?</p>