validate method

@override bool validate(T? value, Map<String, FormFieldState> fields)

Validates the given value against the validation rule.

• value: The value to be validated.
• fields: A map of form field states for cross-field validation.

Returns true if the validation passes, false otherwise.

Implementation

@override
bool validate(T? value, Map<String, FormFieldState> fields) {
  return value != null && value.length <= max;
}