title: Create UIView with custom shape
body: <p>So I was wondering if there's a way to make a UIView with a custom shape. </p>
  
  <p>I'm trying to make a piano keyboard so when the user touches the view a delegate method responds by playing a noise. The picture is a .png with the picture of the key and a transparent background.</p>
  
  <p>Thanks in advance.</p>