trackColor property
Color of the track.
Defaults to Colors.grey.
Widget build(BuildContext context) {
  return SfCartesianChart(
    series: <BarSeries<SalesData, num>>[
      BarSeries<SalesData, num>(
        isTrackVisible: true,
        trackColor: Colors.red
      ),
    ],
  );
}
Implementation
final Color trackColor;