title: Nested, collapsing sidebar nav with Bootstrap, Scrollspy, and Collapse?
body: <p>I'd like to create sidebar navigation with subnavigation that appears when a user enters the parent section on the page:</p>
  
  <p>eg <a href="https://parse.com/docs/ios_guide#queries/iOS" rel="nofollow noreferrer">https://parse.com/docs/ios_guide#queries/iOS</a></p>
  
  <p><img src="https://i.stack.imgur.com/FzJd5.jpg" alt="enter image description here"></p>
  
  <p>I think the way to do it with bootstrap is a combination of the <code>affix</code>, <code>scrollspy</code> and <code>collapse</code> plugins, but I'm not sure how to fire the correct <code>collapse</code> event when the user scrolls into or clicks into the correct parent section.</p>