curveColor property
Color of the normal distribution spline curve.
Defaults to Colors.blue.
Widget build(BuildContext context) {
  return SfCartesianChart(
    series: <HistogramSeries<SalesData, num>>[
      HistogramSeries<SalesData, num>(
        curveColor: Colors.red
      ),
    ],
  );
}
Implementation
final Color curveColor;