Issues trying to edit my frontend while reading estimote Beacons

Hi EveryOne!

Im new on beacons develop! ( and also in android develop…) , I just did the BackGround Monitoring sample and it works fine for me.

The troubles begin when I try to edit my frontEnd because all my widgets, items and all that stuff are on my MainActivity class and I cant get access from the application extends (The one its needed for estimote BackGround monitoring).

How can I edit, for example, a TextView while reading de entrance of a beacon on "onEnteredRegion"
Thanks for all!