title: Using blocks to pass data back to view controller
body: <p>I was looking at <a href="https://stackoverflow.com/questions/5210535/passing-data-between-view-controllers">this question</a>.</p>
  
  <p>One of the answers shows how to use blocks to pass data backwards view the <code>prepareForSegue</code> method. My understanding is this method should really be used to pass data forward, not backwards. </p>
  
  <p>I'm wanting to try blocks out for this purpose - passing data back to another viewController. </p>
  
  <p>My question is: How do I do this, without using <code>prepareForSegue</code> method? 
  I could use for instance in a UITableView - <code>didselectRowAtIndexPath</code> and dismiss the view - but then how does the receiving view get "notified" there is data to come back, without using a delegate? </p>