highPointColor property Null safety

Color? highPointColor

Customizes the marker color of the highest data point.

When the high data point is the first or last data point of the provided data set, then either the first or last point color gets applied.

Defaults to null.

Widget build(BuildContext context) {
 return Scaffold(
   body: Center(
       child: SfSparkAreaChart(
     marker: SparkChartMarker(displayMode: SparkChartMarkerDisplayMode.all),
     highPointColor: Colors.red,
     data: <double>[18, 24, 30, 14, 28],


final Color? highPointColor;