title: how to remove border line in custom uiview?
body: <p><a href="https://i.stack.imgur.com/Vl6v2.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Vl6v2.png" alt="enter image description here"></a></p>
  
  <p>I made a custom view and I called it in UINavigationController, I made it transparent but after I put it inside navigation controller I got that border, how to remove it? 
  thanks in advance </p>