Kiosk mode for tv app

Question

I've integrated kiosk mode for an android app that runs on TV using http://www.andreas-schrade.de/2015/02/16/android-tutorial-how-to-create-a-kiosk-mode-in-android/. As per the kiosk mode only my app is opening on boot completion.But the problem is it is allowing home and back button through remote that escapes my app from homescreen.I want to show my app only in the device.As per customer requirements user should not allowed to open any other apps.Only one app should run on the TV screen.How to do it?