Dead simple badge using custom single child layout

badge.dart

class RecommendedBadge extends StatelessWidget {
  const RecommendedBadge({super.key});

  @override
  Widget build(BuildContext context) => DecoratedBox(
        decoration: BoxDecoration(
          color: Colors.of(context).tertiary,
          borderRadius: BorderRadius.circular(4),
        ),
        child: Padding(
          padding: const EdgeInsets.symmetric(horizontal: 4, vertical: 2),
          child: Text.labelSmall(
            'RECOMMENDED',
            color: Colors.of(context).onTertiary,
          ),
        ),
      );
}

class _BadgeCustomSingleChildLayout extends SingleChildLayoutDelegate {
  _BadgeCustomSingleChildLayout({required this.alignment});

  final Alignment alignment;

  @override
  BoxConstraints getConstraintsForChild(BoxConstraints constraints) => constraints.loosen();

  @override
  Offset getPositionForChild(Size size, Size childSize) =>
      alignment.alongSize(size) - alignment.alongSize(childSize) - Offset(0, childSize.height / 2);

  @override
  bool shouldRelayout(covariant _BadgeCustomSingleChildLayout oldDelegate) =>
      alignment != oldDelegate.alignment;
}