MainActivity is too big. How do I split it into multiple files

Question

I'm building an Android App which has a complex screen with lots of logic.
It currently contains a listview, tabs, search box, and a panel for updating user stuff.
The probem is that the mainactivity code file became very big, although I'm seperating things to different layers, because there's a lot of UI components which affect things in the screen.

I'm trying to seperate it to several files but I don't seem to do it right.
As much as I understood Fragments is not what I need here. Are there any other ways?
Just need some directions please.

I'm asking mostly about the code, not the layout (Although I don't care changing the layout too).

Currently it's 616 lines and the biggest problem is that we are a team and the maintenance became hell...

Answer 1

Create utility class and put your listeners and adapters there. Use main activity only to initialise view instances and setting listeners and adapters.

Answer 2

Although 616 is not a particularly big file you could use Fragments as they just add another layer of abstraction. They also have a similar lifecycle to activities.

This tutorial shows how to add fragments to tabs

http://developer.android.com/training/implementing-navigation/lateral.html