Is MainScreen compulsory in BlackBerry applications?

Question

Currently I've got 2 screens utilizing almost the same functionality and I'd rather extract common logic into some base class but the extend different RIM UI clases: MainScreen and FullScreen. Due to there's no multiple inheritance in java I cant figure out how to do this unless they both extend FullScreen. So the question stated in title arises. I've tested with 4.2 simulator and it works ok without the MainScreen, but I'm not sure for all the OS's out there. Does anyone know?

Cross-posts:

http://supportforums.blackberry.com/t5/Java-Development/Is-MainScreen-compulsory-in-BlackBerry-applications/td-p/383883

http://www.blackberryforums.com/developer-forum/211205-mainscreen-compulsory-blackberry-applications.html#post1511361

Answer 1

Simply put, no it is not mandatory to have MainScreen in Blackberry applications.