title: which UITabBarController event to reload a view?
body: <p>I've got a window with a UITabBarcontroller at the bottom.  I have 3 tabs, corresponding to their respective views. </p>
  
  <p>Everytime I switch to a view via tapping on the tab, i want it to reload.  Which event do I need to tap into?  Where would I do this? </p>
  
  <p>thanks!</p>