code: @Nullable
      private CharSequence formatBreadCrumbTitle(@Nullable final CharSequence breadCrumbTitle) {
          if (!TextUtils.isEmpty(breadCrumbTitle) && isButtonBarShown() &&
                  navigationFragment != null) {
              String format = getProgressFormat();
              int selectedNavigationPreferenceIndex =
                      navigationFragment.getSelectedNavigationPreferenceIndex();
  
              if (!TextUtils.isEmpty(format) && selectedNavigationPreferenceIndex != -1) {
                  int currentStep = selectedNavigationPreferenceIndex + 1;
                  int totalSteps = navigationFragment.getNavigationPreferenceCount();
                  return String.format(format, currentStep, totalSteps, breadCrumbTitle);
              }
          }
  
          return breadCrumbTitle;
      }
docs: Formats a specific bread crumb title, depending on whether the activity is used as a wizard
  and whether the progress should be shown, or not.
  
  @param breadCrumbTitle
  The bread crumb title, which should be formatted, as an instance of the class {@link
  CharSequence} or null, if no bread crumb title should be shown
  @return The formatted bread crumb title as an instance of the class {@link CharSequence} or
  null, if no bread crumb title should be shown