code: @SuppressWarnings({"WeakerAccess", "unused"}) // For library users
      public void registerFilters(@NonNull ViewGroup rootView) {
          final List<AlgoliaFilter> filterViews = LayoutViews.findByClass(rootView, AlgoliaFilter.class);
          if (filterViews.isEmpty()) {
              throw new IllegalStateException(String.format(Errors.LAYOUT_MISSING_ALGOLIAFILTER, rootView));
          }
          registerFilters(filterViews);
          processAllListeners(rootView);
      }
docs: TODO: Ensure developer calls before displaying widget!
  Registers your {@link AlgoliaFilter facet filters}, adding them to this InstantSearch's widgets.
  
  @param rootView a ViewGroup containing one or several {@link AlgoliaFilter AlgoliaFilters}.