Simply vibrate when there is any incoming call when you are in a call already.
It would also vibrate once for any incoming SMS, during your phone call.
Just for my workaround.
-Vibrate Pattern is according to the Android Vibrate API. You can find more info from Google Android.
-Vibrate Repeat is about the PATTERN INDEX that the vibrate should repeat. Just leave it as default "0" is okay.
-ADDED Vibrate for SMS (during phone call only).
Fixed NullPointerException when onStartCommand() received null Intent.