I have this abstract class

abstract class DrawObject {
  Path _path = Path();
  Color _color = Colors.black;
  double _strokeWidth = 2;
  PaintingStyle _paintingStyle = PaintingStyle.stroke;

  DrawObject({Color? color, double? strokeWidth}) {
    _color = color ?? Colors.black;
    _strokeWidth = strokeWidth ?? 2;
  }
}

and this extend

class Circle extends Shape {
  Circle({
    Color? color,
    required super.offset,
    required super.size,
    required double strokeWidth,
  }) : super() {
    _color = color ?? Colors.black; // this line
    _path = setPath();
    _strokeWidth = strokeWidth;
  }
}

Now I have to check null for every shape I created.

Can I use abstract class constructor for define the default value only once?

It’s dart btw