public void setItemSorting(final ItemSorting ITEM_SORTING) {
        if (null == itemSorting) {
            _itemSorting = ITEM_SORTING;
            fireTileEvent(DATA_EVENT);
        } else {
            if (!itemSorting.isBound()) {
                itemSorting.set(ITEM_SORTING);
            }
        }
    }
Defines an optional node that can be used in combination with the
CustomTileSkin.
@param GRAPHIC
src/main/java/eu/hansolo/tilesfx/Tile.java