@Override
 public SwipeBackLayout getSwipeBackLayout() {
   return mHelper.getSwipeBackLayout();
 }
 @Override
 protected void onPostCreate(Bundle savedInstanceState) {
   super.onPostCreate(savedInstanceState);
   mHelper.onPostCreate();
 }
 @Override
 public View findViewById(int id) {
   View v = super.findViewById(id);
   if (v == null && mHelper != null) return mHelper.findViewById(id);
   return v;
 }
 @Override
 protected void onCreate(Bundle savedInstanceState) {
   super.onCreate(savedInstanceState);
   mHelper = new SwipeBackActivityHelper(this);
   mHelper.onActivityCreate();
 }