requiredWhen method

String? Function(String?) requiredWhen(
  1. bool condition(), {
  2. String? msg,
})

Implementation

String? Function(String?) requiredWhen(
  bool Function() condition, {
  String? msg,
}) {
  return (value) {
    if (condition() && (value == null || value.trim().isEmpty)) {
      return msg ?? messages.required;
    }
    return null;
  };
}