You should make your BaseActivity as an Abstract class. No need to register such Activities in manifest, they are just simple java classes extending Activity class not an Activity of your application.
public abstract class BaseActivity extends Activity {
@Override
public void onCreate(bundle) {
super.onCreate(bundle);
setContentView(getLayoutResourceId());
}
protected abstract int yourmethods();
}
public class Activity1 extends BaseActivity {
@Override
public void onCreate(bundle) {
super.onCreate(bundle);
// do extra stuff on your resources, using findViewById on your layout_for_activity1
}
@Override
protected int yourmethod() {
//implemetation
}
}