validate abstract method

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

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

FutureOr<ValidationResult?> validate(
    BuildContext context, T? value, FormValidationMode lifecycle);