shadowColor property

Color of the tooltip shadow.

Defaults to null.

late TooltipBehavior tooltipBehavior;

void initState() {
  tooltipBehavior = TooltipBehavior(
    enable: true,
    shadowColor: Colors.green
  );
  super.initState();
}

Widget build(BuildContext context) {
  return SfCartesianChart(
    tooltipBehavior: tooltipBehavior
  );
}