equals method Null safety

Validator equals(
  1. TextEditingController controller,
  2. {String message = "Validator.equals"}
)

Returns a Validator that accepts a value that is equal to the controller's text.

Implementation

Validator equals(
  TextEditingController controller, {
  String message = "Validator.equals",
}) {
  return add(
    (value) => value != controller.text ? message : null,
  );
}