gapRatio property
Gap ratio between the segments of pyramid. Ranges from 0 to 1.
Defaults to 0.
Widget build(BuildContext context) {
   return Container(
       child: SfPyramidChart(
           series: PyramidSeries<ChartData, String>(
              gapRatio: 0.3
           )
       )
   );
}
Implementation
final double gapRatio;