RoundedRectangleBorder constructor

const RoundedRectangleBorder({BorderSide side: BorderSide.none, BorderRadiusGeometry borderRadius: BorderRadius.zero })

Creates a rounded rectangle border.

The arguments must not be null.

Implementation 

const RoundedRectangleBorder({
  this.side = BorderSide.none,
  this.borderRadius = BorderRadius.zero,
}) : assert(side != null),
     assert(borderRadius != null);