public void setChartGridColor(final Color COLOR) {
        if (null == chartGridColor) {
            _chartGridColor = COLOR;
            fireTileEvent(REDRAW_EVENT);
        } else {
            if (!chartGridColor.isBound()) {
                chartGridColor.set(COLOR);
            }
        }
    }
Defines the color that will be used to colorize lines in
charts e.g. the grid in the RadarChartTileSkin
@param COLOR
src/main/java/eu/hansolo/tilesfx/Tile.java