validate method

  1. @override
FutureOr<ValidationResult?> validate(
  1. BuildContext context,
  2. T? value,
  3. FormValidationMode state
)
override

Validates the given value and returns a validation result.

This method performs the actual validation logic and should return null if the value is valid, or a ValidationResult describing the validation error if invalid.

Parameters:

  • context (BuildContext): The build context for localization access
  • value (T?): The value to validate (may be null)
  • lifecycle (FormValidationMode): The current validation trigger mode

Returns a FutureOr<ValidationResult?> that is null for valid values or contains error information for invalid values.

Implementation

@override
FutureOr<ValidationResult?> validate(
  BuildContext context,
  T? value,
  FormValidationMode state,
) {
  if (value == null) {
    return null;
  }
  if (inclusive) {
    if (value > max) {
      return InvalidResult(
        message ??
            Localizations.of(
              context,
              ShadcnLocalizations,
            ).formLessThanOrEqualTo(_describeValue(max)),
        state: state,
      );
    }
  } else {
    if (value >= max) {
      return InvalidResult(
        message ??
            ShadcnLocalizations.of(context).formLessThan(_describeValue(max)),
        state: state,
      );
    }
  }
  return null;
}