customizeSegment method
Changes the series color, border color, and border width.
Implementation
@override
void customizeSegment(ChartSegment segment) {
final RangeAreaSegment<T, D> rangeAreaSegment =
segment as RangeAreaSegment<T, D>;
updateSegmentColor(rangeAreaSegment, borderColor, borderWidth);
updateSegmentGradient(rangeAreaSegment,
gradientBounds: rangeAreaSegment._fillPath.getBounds(),
gradient: gradient,
borderGradient: borderGradient);
}