I have a counter with a price and buttons with price increment and decrement. I do it all through bloc, but I ran into an error that when I click on the buttons, my price does not change. Accordingly, the state does not change, as I understand it. What exactly is the reason and how can I fix the error so that the price changes when you click on the buttons?

price_counter

class PriceCounter extends StatelessWidget {
  PriceCounter({Key? key, required this.price}) : super(key: key);
  double price = 0.13;

  @override
  Widget build(BuildContext context) {
    final FilterPriceCubit cubit = BlocProvider.of<FilterPriceCubit>(context);

    return BlocBuilder<FilterPriceCubit, FilterPriceState>(
      builder: (context, state) {
        if (state is FilterPriceInitial) {
          state.fitlerPrice = price;
          return Padding(
            padding: const EdgeInsets.symmetric(horizontal: 21),
            child: Row(
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                IconButton(
                  onPressed: () =>
                      cubit.priceFilterDecrement(state.fitlerPrice),
                  icon: SvgPicture.asset(constants.Assets.minus),
                  constraints: const BoxConstraints(),
                  padding: EdgeInsets.zero,
                ),
                const SizedBox(width: 20),
                InputFieldPrice(
                    price: state.fitlerPrice,
                    textStyle: constants.Styles.normalBookTextStyleWhite),
                const SizedBox(width: 20),
                IconButton(
                  onPressed: () =>
                      cubit.priceFilterIncrement(state.fitlerPrice),
                  icon: SvgPicture.asset(constants.Assets.plus),
                  constraints: const BoxConstraints(),
                  padding: EdgeInsets.zero,
                ),
              ],
            ),
          );
        }
        return const SizedBox();
      },
    );
  }
}

input_fields_price

class InputFieldPrice extends StatefulWidget {
  final double price;
  final TextStyle textStyle;

  const InputFieldPrice(
      {Key? key, required this.price, required this.textStyle})
      : super(key: key);

  @override
  State<InputFieldPrice> createState() => _InputFieldPrice();
}

class _InputFieldPrice extends State<InputFieldPrice> {
  final _formKey = GlobalKey<FormState>();
  final _priceController = TextEditingController();

  @override
  void dispose() {
    _priceController.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) => SizedBox(
        width: 100,
        child: Form(
          key: _formKey,
          child: TextFormField(
            keyboardType: TextInputType.number,
            controller: _priceController
              ..text = widget.price.toStringAsFixed(2),
            style: widget.textStyle,
            textAlign: TextAlign.center,
            decoration: InputDecoration(
              prefix: Text('JC', style: widget.textStyle),
              suffix: const Text(
                'KWh',
                style: constants.Styles.smallerBookTextStyleWhite,
              ),
              contentPadding: EdgeInsets.zero,
              border: InputBorder.none,
            ),
            inputFormatters: [
              LengthLimitingTextInputFormatter(4),
              FilteringTextInputFormatter.allow(RegExp("[0-9.]")),
            ],
          ),
        ),
      );
}

price_cubit

class FilterPriceCubit extends Cubit<FilterPriceState> {
  FilterPriceCubit() : super(FilterPriceInitial(0.15));

  void priceFilterIncrement(double priceFilter) {
    double priceIncrement = priceFilter   0.01;
    emit(FilterPriceInitial(priceIncrement));
  }

  void priceFilterDecrement(double priceFilter) {
    double priceDecrement =
        priceFilter >= 0.01 ? priceFilter - 0.01 : priceFilter - 0;
    emit(FilterPriceInitial(priceDecrement));
  }
}

price_state_cubit

abstract class FilterPriceState {}

class FilterPriceInitial extends FilterPriceState {
  double fitlerPrice;
  FilterPriceInitial(this.fitlerPrice);
}

CodePudding user response：

Everytime the bloc builder is called the state.fitlerPrice is set to price. Please remove this from bloc builder. Rest everything seems to be good.

state.fitlerPrice = price;