radius property Null safety
final
The Radius of the scrollbar thumb's rounded rectangle corners.
If null, the default value is platform dependent. On TargetPlatform.android, no radius is applied to the scrollbar thumb. On TargetPlatform.iOS, CupertinoScrollbar.defaultRadius is used. The remaining platforms have a default Radius.circular of 8.0 pixels.
Implementation
final Radius? radius;