code: protected final void waitOnSharedElementNamed(@NonNull String name) {
          if (!sharedElementNames.values().contains(name)) {
              throw new IllegalStateException("Can't wait on a shared element that hasn't been registered using addSharedElement");
          }
          waitForTransitionNames.add(name);
      }
docs: The transition will be delayed until the view with the name passed in is available in the "to" hierarchy. This is
  particularly useful for views that don't load instantly, like RecyclerViews. Note that using this method can
  potentially lock up your app indefinitely if the view never loads!