validateValue method
Validates the value.
Returns null
if the value is valid, otherwise an error message.
Call validate() instead of this method when using the validator.
Implementation
@override
String? validateValue(T? valueCandidate) {
String? errorResult;
for (final FormFieldValidator<T> validator in validators) {
final String? validatorResult = validator.call(valueCandidate);
if (validatorResult == null) {
return null;
} else {
errorResult = validatorResult;
}
}
return errorResult;
}