flutter_field_validator

Description:

flutter field validator

A simple field validator for Flutter #
Can be expanded upon fairly easily, you can create your own custom validators by inheriting the FieldValidatorCore.
How to use #
It is fairly simple, you instantiate a FieldValidator, pass in the validators and call validate.
// Flutter TextFormField using the FieldValidator
return TextFormField(
autovalidateMode: AutovalidateMode.onUserInteraction,
validator: (text) => FieldValidator(
[
RequiredFieldValidator(
errorMessage: "Field required",
),
LengthFieldValidator(
minLength: 4,
errorMessage: "Field needs at least 4 characters",
),
LengthFieldValidator(
maxLength: 12,
errorMessage: "Field can have up to 12 characters",
),
PatternFieldValidator(
r"(^[a-z])([a-z0-9-]*)([a-z0-9]$)",
errorMessage: "Use only lowercase letters hyphens and numbers",
),
ConditionFieldValidator(
(field) => field == "type this",
errorMessage: "You have to type type this",
),
],
field: text,
).validate(),
);
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