Is declaring a class that extends Activity inside another Activity class possible? If it is, how would I register that class in the manifest? Also, is that something that ca
Yes, it does work -- it is just another class -- you just need to declare your activity using inner class notation in AndroidManifest.xml:
Seems to work fine for me, but perhaps when this question was asked, it wasn't supported in older versions of Android?
Not sure WHY you'd want to do this, but you can.