FormzInput<T, E> class abstract

A FormzInput represents the value of a single form input field. It contains information about the value as well as validity.

FormzInput should be extended to define custom FormzInput instances.

enum FirstNameError { empty }
class FirstName extends FormzInput<String, FirstNameError> {
  const FirstName.pure({String value = ''}) : super.pure(value);
  const FirstName.dirty({String value = ''}) : super.dirty(value);

  FirstNameError? validator(String value) {
    return value.isEmpty ? FirstNameError.empty : null;
  • @immutable


FormzInput.dirty(T value)
Constructor which create a dirty FormzInput with a given value.
FormzInput.pure(T value)
Constructor which create a pure FormzInput with a given value.


displayError → E?
The error to display if the FormzInput value is not valid and has been modified.
no setter
error → E?
Returns a validation error if the FormzInput is invalid. Returns null if the FormzInput is valid.
no setter
hashCode int
The hash code for this object.
no setteroverride
isNotValid bool
Whether the FormzInput value is not valid. A value is invalid when the overridden validator returns an error (non-null value).
no setter
isPure bool
If the FormzInput is pure (has been touched/modified). Typically when the FormzInput is initially created, it is created using the FormzInput.pure constructor to signify that the user has not modified it.
isValid bool
Whether the FormzInput value is valid according to the overridden validator.
no setter
runtimeType Type
A representation of the runtime type of the object.
no setterinherited
value → T
The value of the given FormzInput. For example, if you have a FormzInput for FirstName, the value could be 'Joe'.


noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
toString() String
A string representation of this object.
validator(T value) → E?
A function that must return a validation error if the provided value is invalid and null otherwise.


operator ==(Object other) bool
The equality operator.