onTrackballPositionChanging property Null safety

ChartTrackballCallback? onTrackballPositionChanging
final

Occurs while the trackball position is changed. Here, you can customize the text of the trackball.

Widget build(BuildContext context) {
   return Container(
       child: SfCartesianChart(
           trackballBehavior: TrackballBehavior(enable: true),
           onTrackballPositionChanging: (TrackballArgs args) => trackball(args)
       ));
}
void trackball(TrackballArgs args) {
   args.chartPointInfo = ChartPointInfo();
}

Implementation

final ChartTrackballCallback? onTrackballPositionChanging;