How to cancel required text (required this) in Flutter?

Question

My Flutter source code has these lines to control how users updating their profile:

class _TwoButtonWidget extends StatelessWidget {
  const _TwoButtonWidget({
    required this.userProvider,
    required this.userNameController,
    required this.emailController,
    required this.phoneController,
    required this.aboutMeController,
    required this.addressController,
    required this.cityController,
  });

  final TextEditingController userNameController;
  final TextEditingController emailController;
  final TextEditingController phoneController;
  final TextEditingController aboutMeController;
  final TextEditingController addressController;
  final TextEditingController cityController;
  final UserProvider userProvider;

Look at "cityController": Users have to put information to a required field named City.

Now I don't want City field is a required field so users could leave it blank.

So what have I to do next? Can you share me some lines to change this attribute?

Thank you very much!

Answer 1

You can make nullable

 final TextEditingController? cityController;

Now you can remove required

class _TowButtonWidget extends StatelessWidget {
  const _TowButtonWidget({
    Key? key,
    required this.userNameController,
    required this.emailController,
    required this.phoneController,
    required this.aboutMeController,
    required this.addressController,
    this.cityController,
    required this.userProvider,
  }) : super(key: key);

  final TextEditingController userNameController;
  final TextEditingController emailController;
  final TextEditingController phoneController;
  final TextEditingController aboutMeController;
  final TextEditingController addressController;
  final TextEditingController? cityController;
  final UserProvider userProvider;

More about null-safety