when<TResult extends Object?> method Null safety

  1. @optionalTypeArgs
TResult when<TResult extends Object?>(
  1. {required TResult count(
    1. int crossAxisCount,
    2. double mainAxisSpacing,
    3. double crossAxisSpacing,
    4. double childAspectRatio,
    5. double? mainAxisExtent
    ),
  2. required TResult extend(
    1. double maxCrossAxisExtent,
    2. double mainAxisSpacing,
    3. double crossAxisSpacing,
    4. double childAspectRatio,
    5. double? mainAxisExtent
    )}
)
@optionalTypeArgs, inherited

Implementation

@optionalTypeArgs
TResult when<TResult extends Object?>({
  required TResult Function(
          int crossAxisCount,
          double mainAxisSpacing,
          double crossAxisSpacing,
          double childAspectRatio,
          double? mainAxisExtent)
      count,
  required TResult Function(
          double maxCrossAxisExtent,
          double mainAxisSpacing,
          double crossAxisSpacing,
          double childAspectRatio,
          double? mainAxisExtent)
      extend,
}) =>
    throw _privateConstructorUsedError;