title: How to get a height a UITextView should be given width and length of text?
body: <p>I am adding a UIView that contains a UITextView which is constrained to the top, left, and bottom of the view.</p>
  
  <p>The width of the UIView should be the screen size's width which in turn will be the UITextView's width.</p>
  
  <p>When I go to create this UIView, I can make it's CGSize to the screen size's width, but I am not sure on how to calculate the height.</p>
  
  <p>How can I figure out what height I must set this UIView so that the UITextView can properly show? Is there a way I can figure out the number of lines a UITextView would have given a certain width?</p>