title: how to find out which activity had started intent ,in my activity in android
body: <p>i am trying to get the intent,which activity had started
   the intent, i am trying facebook integration with my app,in which i
   want to know who have called my activity is the call from facebook or
   withen my app, suppose i have 3 activity a,b &amp; c, a call b c call b
   facebook calls b here in activity i want to detect who have started
   activity b how to get this, i googled it but no use please share yours
   views on this or any refrence thank you</p>