title: Activity.findViewById returning null sporadically
body: <p>From the crash logs that I am getting from the Android market, I can see
  that some of my users are getting Force Closes caused by
  NullPointerExceptions when my code tries to access views that are in my
  application.  In one example, my activity makes a call to findViewById()
  in onCreate() after I call setContentView().  I get an NPE when I try to
  access the view after the call to findViewById() (still in onCreate).
  What has me really scratching my head is that this does not happen all
  of the time (in fact most of the time the code acts as I would expect),
  but enough to have me concerned.</p>
  
  <p>I could add code to <em>always</em> check for null and avoid the NPE, but I
  would like to understand what could be causing the sporadic behavior.</p>
  
  <p>Does anyone know what could be causing this?</p>