validate method

@override FutureOr<ValidationResult?> validate(BuildContext context, String? value, FormValidationMode state)

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, String? value, FormValidationMode state) {
  if (value == null) {
    return null;
  }
  if (!pattern.hasMatch(value)) {
    return InvalidResult(
        message ??
            Localizations.of(context, ShadcnLocalizations).invalidValue,
        state: state);
  }
  return null;
}