code: public final void setDivider(final int index, @Nullable final CharSequence title) {
          Divider divider = new Divider();
          divider.setTitle(title);
          adapter.set(index, divider);
          adaptGridViewHeight();
      }
docs: Replaces the item at a specific index with a divider.
  
  @param index
  The index of the item, which should be replaced, as an {@link Integer} value
  @param title
  The title of the divider, which should be added, as an instance of the type {@link
  CharSequence}, or null, if no title should be used