calculateConstraints function

Implementation

BoxConstraints calculateConstraints(Size size, BoxSpec spec) {
  final padding = spec.padding ?? EdgeInsets.zero;
  final margin = spec.margin ?? EdgeInsets.zero;

  double horizontalBorder = 0.0;
  double verticalBorder = 0.0;

  if (spec.decoration is BoxDecoration) {
    final border = (spec.decoration as BoxDecoration).border;
    if (border != null) {
      horizontalBorder = border.dimensions.horizontal;
      verticalBorder = border.dimensions.vertical;
    }
  }

  final horizontalSpacing =
      padding.horizontal + margin.horizontal + horizontalBorder;
  final verticalSpacing = padding.vertical + margin.vertical + verticalBorder;

  return BoxConstraints(
    maxHeight: size.height - verticalSpacing,
    maxWidth: size.width - horizontalSpacing,
  );
}