I am new to Android and have some questions about how to handle I so called "Subroutines".
My main.java is to handle user input and to display the results. I group other "subroutines" such as
some mathematical calculations like converting Gregorian Day to Julian Day, into a separate class.
I have the following questions:-
1) Should I use class "implement" "interface"?
2) Should I use class "Activity"?
3) How do I pass arguments to the called subroutine and retrieve values back to Main.java?
4) Can the subroutines within the that class to call each other ?
Yes, a very basic stuff, but would appreciate it if anyone could offer some help or point me in
the right direction to find the solutions.