title: Custom animation during pull to refresh
body: <p>I'm trying to customize an Pull To Refresh view. I'm wondering how to make something similar to below animation?</p>
  
  <p><a href="https://i.stack.imgur.com/tlx4d.gif" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/tlx4d.gif" alt="enter image description here"></a><br>
  <sub>(source: <a href="https://d13yacurqjgara.cloudfront.net/users/188232/screenshots/1956070/open-uri20150303-11-rtr4op" rel="nofollow noreferrer">cloudfront.net</a>)</sub>  </p>