RequiredRule class

Validates that a field is not empty.

Implemented types

• MyFormFieldValidationRule

Annotations

• @immutable

Constructors

RequiredRule.new({String? message})

Creates a required validation rule. message is the error message displayed if the field is empty.

const

Properties

hashCode → int

The hash code for this object.

no setter, inherited

message → String

final

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

Methods

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

toString() → String

A string representation of this object.

inherited

validate(String? value, {BuildContext? context}) → String?

Validates the given value. Returns an error message String if validation fails, otherwise returns `null].

override

Operators

operator ==(Object other) → bool

The equality operator.

inherited