title: IOS constraints - Shrink vertical spacing according to view size
body: <p>I have this view with a button and a label:</p>
  <p><img src="https://i.stack.imgur.com/8TuuT.jpg" alt="open" /></p>
  <p>which is in a given size.</p>
  <p>I want to make the spacing between the button and the label dynamic, meaning that when the view height is change, the spacing changes as well.</p>
  <p>for a example:
  <img src="https://i.stack.imgur.com/3aPXz.png" alt="close" /></p>
  <p>how can i do that ?</p>