How to access a variable present in state in cubit in flutter?

Question

I am using cubit for state management in my app. I have a variable in the state called prices which I want to access:

Future<void> fetchMonthlyTotals(String userId) async {
    //var userId = await getUserId();
    var prices =
        await myDB().getPrices(userId);
    print(prices .toString());
    // ignore: unnecessary_null_comparison
    if (prices != null && prices .isNotEmpty) {
      emit(MonthlyTotalsState(monthlyTotals: prices ));
    } else {
      debugPrint("prices is empty");
    }
  }

This is the class where I want to access prices variable:

void getExpenses() async {
    var prices = //get price from cubit
    print(prices);
}

Both the codes are in different classes and are present in the same package

How do I access the price variable?

Kindly comment if more information is needed.

score 2 · Answer 1 · answered Apr 12 '22 at 19:57

You can use like this aswell

BlocBuilder<Cubit, CubitState>(
  buildWhen: (previous, current) => current is MonthlyTotalsState     
    builder: (context, state) {
      if(state is MonthlyTotalsState){
       return Center(
         child: Text('Monthly TotalPrices:${state.monthlyTotals}'),
         );
       }
       return const SizedBox();
    },
  ),

score 1 · Answer 2 · answered Apr 12 '22 at 14:22

1

If you need to use this value inside the UI you should use a CubitBuilder. It will update your UI whenever the state changes.

CubitBuilder<ReportinCubit, MonthlyTotalsState>(
        builder: (_, monthlyTotalState) {
          return Center(
            child: Text('Monthly Total Prices: ${monthlyTotalState.prices}'),
          );
        },
      ),

answered Apr 12 '22 at 14:22

Mark

7,507
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`CubitBuilder` is not getting recognized – Aditya Dixit Apr 12 '22 at 14:23
You can use `BlocBuilder` instead, that's what I always use, didn't even know there was a `CubitBuilder` – TheUltimateOptimist Apr 12 '22 at 14:26
Sorry, my fault. `CubitBuilder` is now deprecated (for a long time). Now everything can be handled with a `BlocBuilder` :) – Mark Apr 12 '22 at 14:43

score 1 · Accepted Answer · answered Apr 12 '22 at 14:33

1

If you need to use this value inside the UI you should use a BlocBuilder. It will update your UI whenever the state changes. If you however want to do something like showing a dialog or navigating in response to a state change you should use a BlocListener. If you want to do a combination of both of the mentioned use-cases you can use a BlocConsumer

BlocBuilder<ReportinCubit, MonthlyTotalsState>(
        builder: (_, monthlyTotalState) {
          return Center(
            child: Text('Monthly Total Prices: ${monthlyTotalState.prices}'),
          );
        },
      ),

answered Apr 12 '22 at 14:33

TheUltimateOptimist

1,089
4
19

What is `ReportinCubit`? – Aditya Dixit Apr 12 '22 at 15:00
Nothing more than the name of the cubit, you are using, whose state you want to have access to – TheUltimateOptimist Apr 12 '22 at 15:08

How to access a variable present in state in cubit in flutter?

3 Answers3