Which one is better option for maintaining application or activities?

Question

Which one is better option for application or activities?

A. BaseActivity class, [OR]

B.Singleton class.

In my application most of activities do same actions like show toasts, maintaining sessions, static variables,show EditText errors, HTTP request/response, etc., For now I'm extends BaseActivity in all my Activities where needed.

Answer 1

You're on the right path, a BaseClass is preferred because most of those thing you mentioned (Manipulating Toasts, EditText functions) require a Context to work with. A Singleton class would need that Context passed to it with every method call - a BaseClass does not (since it is technically a Context itself).

Answer 2

These are two fundermental different design patterns.

1. BaseActivity --> Inheritance
2. Use a Singleton in all activities --> Aggregate pattern

You find many posts in the internet about advantage and disadvantage of both patterns.

For your specific problem I would suggest to use inheritance. It is a common way to do and you should avoid to use the singleton pattern if possible.