ScrollBar constructor Null safety

const ScrollBar(
  1. {Key? key,
  2. required Widget child,
  3. bool? thumbVisibility,
  4. bool? trackVisibility,
  5. double? thickness,
  6. Radius? radius,
  7. bool? interactive,
  8. ScrollbarOrientation? scrollbarOrientation}
)

Implementation

const factory ScrollBar(
    {final Key? key,
    required final Widget child,
    final bool? thumbVisibility,
    final bool? trackVisibility,
    final double? thickness,
    final Radius? radius,
    final bool? interactive,
    final ScrollbarOrientation? scrollbarOrientation}) = _$ScrollBar;