How to declare global variables in Android?

Question

I am creating an application which requires login. I created the main and the login activity.

In the main activity onCreate method I added the following

Answer 1

The approach of subclassing has also been used by the BARACUS framework. From my point of view subclassing Application was intended to work with the lifecycles of Android; this is what any Application Container does. Instead of having globals then, I register beans to this context an let them beeing injected into any class manageable by the context. Every injected bean instance actually is a singleton.

See this example for details

Why do manual work if you can have so much more?