pointRadiusMapper property Null safety

ChartIndexedValueMapper<String>? pointRadiusMapper
final

Maps the field name, which will be considered for calculating the radius of all the data points.

Defaults to null.

Widget build(BuildContext context) {
   return Container(
       child: SfCircularChart(
           series: <PieSeries<ChartData, String>>[
             PieSeries<ChartData, String>(
               dataSource: <ChartData>[
                  ChartData('USA', 10, '50%'),
                  ChartData('China', 11, '55%'),
                  ChartData('Russia', 9, '60%'),
                  ChartData('Germany', 10, '65%'),
               ],
               xValueMapper: (ChartData data, _) => data.xVal,
               yValueMapper: (ChartData data, _) => data.yVal,
               pointRadiusMapper: (ChartData data, _) => data.radius,
             ),
          ],
       )
   );
}
class ChartData {
  ChartData(this.xVal, this.yVal, [this.radius]);
  final String xVal;
  final int yVal;
  final String radius;
}

Implementation

final ChartIndexedValueMapper<String>? pointRadiusMapper;