onChartTouchInteractionDown property Null safety

ChartTouchInteractionCallback? onChartTouchInteractionDown
final

Occurs when touched on the chart area.

Widget build(BuildContext context) {
   return Container(
       child: SfCartesianChart(
           onChartTouchInteractionDown: (ChartTouchInteractionArgs args){
              print(args.position.dx.toString());
              print(args.position.dy.toString());
            }
       ));
}

Implementation

final ChartTouchInteractionCallback? onChartTouchInteractionDown;