width property
Width of the annotation.
Defaults to 0%.
Widget build(BuildContext context) {
   return Container(
       child: SfCircularChart(
           annotations: <CircularChartAnnotation>[
               CircularChartAnnotation(
                   width: '10%',
                   widget: const Text('Circular'),
                ),
             ),
           ],
       )
   );
}
Implementation
final String width;