title: Hide button in Swift 3
body: <p>I've just started with coding and I really want to know how to hide buttons.</p>
  
  <p>What I want to do is when I press my button:</p>
  
  <p><strong>Start:</strong> I want to let the start button and the back button disappear.</p>
  
  <p>It's done with Outlets and Actions.</p>
  
  <p>I already searched a bit but when I wanted to do it, it said that the <code>do</code> keyword is expected to designate a block of statements.</p>
  
  <p>I hope someone can help me out.</p>