The prefix 'context' can't be used here because it is shadowed by a local declaration

Question

I have this stateless date of birth input class, read-only. When tapped, it will show a date picker and after the user picked a date, it will send the value to the bloc state, and it will change the state and the value so it shows the picked date from the date picker. This is the code:

class DateOfBirthInput extends StatelessWidget {
  DateOfBirthInput({
    required this.textEditingController,
    required this.focusNode
  });

  final TextEditingController textEditingController;
  final FocusNode focusNode;

  @override
  Widget build(BuildContext context) {
    return BlocBuilder<SignUpBloc, SignUpState>(
      buildWhen: (previous, current) => previous.dateOfBirth != current.dateOfBirth,
      builder: (context, state) {
        return Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Text(
              'Date of Birth',
              style: TextStyle(
                color: Colors.grey[500],
                fontWeight: FontWeight.w600
              )
            ),
            TextFormField(
              enabled: state.formEnabled,
              controller: textEditingController,
              focusNode: focusNode,
              readOnly: true,
              decoration: InputDecoration(
                hintText: '1 January 1990',
                hintStyle: TextStyle(
                  color: Colors.grey[400],
                  fontWeight: FontWeight.w500
                ),
                suffixIcon: Icon(
                  Icons.calendar_today_outlined,
                  size: 24.0,
                  color: Colors.grey[500],
                ),
                errorText: state.dateOfBirthDisplay.invalid ? 'Please enter your date of birth' : null,
                errorStyle: TextStyle(
                  fontSize: 14.0,
                  color: Colors.red,
                  fontWeight: FontWeight.w500
                ),
              ),
              onTap: () async {
                DateTime? datePicker = await showDatePicker(
                  context: context,
                  initialDate: DateTime.now(),
                  firstDate: DateTime(1900, 1),
                  lastDate: DateTime.now()
                );
                if (datePicker != null) {
                  String dateOfBirth = DateFormat('dd MMMM yyyy').format(DateTime.parse(datePicker.toString()));
                  textEditingController.text = dateOfBirth;
                  context.read<SignUpBloc>.add(DateOfBirthChanged(dateOfBirthDisplay: dateOfBirth, dateOfBirth: datePicker));
                }
              }
            ),
          ],
        );
      },
    );
  }
}

In this context, i got an error. This is the context:

context.read<SignUpBloc>.add(DateOfBirthChanged(dateOfBirthDisplay: dateOfBirth, dateOfBirth: datePicker));

This is the error:

The prefix 'context' can't be used here because it is shadowed by a local declaration. Try renaming either the prefix or the local declaration.

I've tried to change one of the contexts, the builder: (context, state), I've changed to builder: (ctx, state), and still get the same error.

Please help.

https://pub.dev/documentation/provider/latest/provider/ReadContext/read.html ...likely you could only use `context` later, once the widget had been built. That's why renaming won't help, but you'll have to ditch that local declaration. — Martin Zeitler, Apr 28 '21 at 08:02
Still no, it's not I'm ignoring the documentation. I've found the solution by the way, It should be `context.read().add`, not `context.read.add`, and it works. Thanks, @MartinZeitler. — Michael Reno Pratama Setyawan, Apr 28 '21 at 08:24
The solution is, it should be `context.read().add`, NOT `context.read.add` — Michael Reno Pratama Setyawan, Jul 24 '21 at 07:31
The `()` is the function call, that may return the instance? — Martin Zeitler, Jul 24 '21 at 11:51

score 1 · Answer 1 · answered Apr 28 '21 at 07:39

1

Currently, you are trying to access the SignupBloc from the signup bloc's builder context, the context variable because both of your stateless widget's context and blocbuilder's context are named as context

Rename one of your contexts to something else, either build(BuildContext context) or builder: (context, state) {

You can rename builder: (ctx, state) then the error should be gone.

answered Apr 28 '21 at 07:39

krishnakumarcn

3,959
6
39
69

Hi, I've tried to change it, and still the same error. – Michael Reno Pratama Setyawan Apr 28 '21 at 07:41

score 0 · Answer 2 · answered Apr 28 '21 at 07:39

0

Try this change.

builder: (ctx, state) {
  //...
  ctx.read<SignUpBloc>.add(DateOfBirthChanged(dateOfBirthDisplay: dateOfBirth, dateOfBirth: datePicker));
},

answered Apr 28 '21 at 07:39

Jigar Patel

4,953
1
12
20

Hi, I've tried to change it, and still the same error. – Michael Reno Pratama Setyawan Apr 28 '21 at 07:41
Make sure you don't change for both these - `Widget build(BuildContext context)` and `builder: (context, state)`. You need to change it for only one of these. – Jigar Patel Apr 28 '21 at 07:44
1

Understood, I only changed the `builder: (context, state)` => `builder: (ctx, state)`, still the same error. – Michael Reno Pratama Setyawan Apr 28 '21 at 07:46

The prefix 'context' can't be used here because it is shadowed by a local declaration

2 Answers2