title: Interface Builder UIButton inside of UITextView
body: <p>I want to build an interface that has scrolling text inside a UITextView, and a basic round rect button at the end of the text. The placement of the button will be dynamic, depending on the length of the text in the textView My view hierarchy is like this:</p>
  
  <ul>
  <li>View Controller
  <ul>
  <li>Text View (UITextView)</li>
  </ul></li>
  </ul>
  
  <p>When I try to add a Round Rect Button to the textView in Interface Builder, it replaces it. Is it correct to add a UIButton as a subview of the UITextView, or should I be doing something else?</p>