public void setOldValueVisible(final boolean VISIBLE) {
        if (null == oldValueVisible) {
            _oldValueVisible = VISIBLE;
            fireTileEvent(VISIBILITY_EVENT);
        } else {
            if (!oldValueVisible.isBound()) {
                oldValueVisible.set(VISIBLE);
            }
        }
    }
Defines if the old value of the tile should be visible (not implemented)

@param VISIBLE
src/main/java/eu/hansolo/tilesfx/Tile.java