I like my UIs to be intuitive; each screen should naturally and unobtrusively guide the user on to the next step in the app. Barring that, I strive to make things as confusi
You could try turning off the main Activity's ability to save its state (thus making it forget what control had text and what had focus). You will need to have some other way of remembering what your EditText's have and repopulating them onResume(). Launch your sub-Activities with startActivityForResult() and create an onActivityResult() handler in your main Activity that will update the EditText's correctly. This way you can set the proper button you want focused onResume() at the same time you repopulate the EditText's by using a myButton.post(new Runnable(){ run() { myButton.requestFocus(); } });
The View.post() method is useful for setting focus initially because that runnable will be executed after the window is created and things settle down, allowing the focus mechanism to function properly by that time. Trying to set focus during onCreate/Start/Resume() usually has issues, I've found.
Please note this is pseudo-code and non-tested, but it's a possible direction you could try.