Laravel 5.1 - Variable in main blade layout

I'm using Laravel 5.1. And I have a problem about variable in my Layout View.

In my Layout view, I use a variable to show an active login user like this one on my DashboardController:

...
class DashboardController extends Controller {

        public function index(Request $request) {
            //
            $title = "Dashboard";
            $userActive = $request->user();
            return view('dashboard.index', compact('title', 'userActive'));
        }
...

The $userActive is to show who is login. My problem is i need to write this (the $userActive) code like above if I use another function, or another Contoller.

How to make it simple by write it only once?

via Chebli Mohamed