public void setMapProvider(final MapProvider PROVIDER) {
        if (null == mapProvider) {
            _mapProvider = PROVIDER;
            fireTileEvent(MAP_PROVIDER_EVENT);
        } else {
            if (!mapProvider.isBound()) {
                mapProvider.set(PROVIDER);
            }
        }
    }
Defines an optional node that can be used in combination with the
CustomTileSkin.
@param GRAPHIC
src/main/java/eu/hansolo/tilesfx/Tile.java