/** Add the @a object with the @a key. */
 public void put(String key, Object object) {
   mRetainedFragment.put(key, object);
 }
 /** Get the object with @a key. */
 @SuppressWarnings("unchecked")
 public <T> T get(String key) {
   return (T) mRetainedFragment.get(key);
 }
 /**
  * Return the Activity the RetainedFragment is attached to or null if it's not currently attached.
  */
 public Activity getActivity() {
   return mRetainedFragment.getActivity();
 }