AppCompat theme for Leanback

You are not allowed to use AppCompat theme for Android TV with Leanback library. You should extend your BaseActivity of the FragmentActivity to benefit from the Support Components.

You can't use Theme.Leanback for Activities extending AppCompatActivity. For using support fragments you can't extend the activity with android.app.Activity either. For using support fragments extend your activity with android.support.v4.app.FragmentActivity.