title: Detect ScrollView has reached the end
body: <p>I have a <code>Text</code> with long text inside a <code>ScrollView</code> and I want to detect when the user has scrolled to the end of the text so I can enable a button.</p>
  
  <p>I've been debugging the event object from the <code>onScroll</code> event but there doesn't seem any value I can use.</p>