onPointLongPress property Null safety

ChartPointInteractionCallback? onPointLongPress
final

Called when long pressed on the chart data point.

The user can fetch the series index, point index, viewport point index and data of the long-pressed data point.

Widget build(BuildContext context) {
   ChartSeriesController _chartSeriesController;
   return Container(
       child: SfCartesianChart(
           series: <LineSeries<SalesData, num>>[
               LineSeries<SalesData, num>(
                   onPointLongPress: (ChartPointDetails details) {
                      print(details.pointIndex);
                   },
               ),
             ],
       ));
}

Implementation

final ChartPointInteractionCallback? onPointLongPress;