single_value_cubit 1.2.3

Simple single value cubit. Works as a simple state manager for inputs, scrolls, flags etc. Works best as injected and observed by other blocs/cubits.

Single value cubit

Just a simple cubit with a state setter. Helpful with inputs, scrolls and single flags scenarios.

Enum state

SingleValueCubit<T> works with any type, including enums. Use it for things like selected tabs, filters, sort order, or theme mode:

enum SortOrder { ascending, descending }

class SortOrderCubit extends SingleValueCubit<SortOrder> {
  SortOrderCubit() : super(SortOrder.ascending);
}

// inside a widget
BlocBuilder<SortOrderCubit, SortOrder>(
  builder: (context, order) {
    return IconButton(
      icon: Icon(
        order == SortOrder.ascending ? Icons.arrow_upward : Icons.arrow_downward,
      ),
      onPressed: () => context.read<SortOrderCubit>().set(
        order == SortOrder.ascending ? SortOrder.descending : SortOrder.ascending,
      ),
    );
  },
)

StringInputCubit

StringInputCubit is a convenience subclass of SingleValueCubit<String> initialized with an empty string. Use it as a base class whenever the state is a text input starting from '':

class SearchQueryCubit extends StringInputCubit {}

Bool Extension

SingleValueBoolCubitExtension adds a toggle() method to any SingleValueCubit<bool>, flipping the current state:

class PasswordVisibilityCubit extends SingleValueCubit<bool> {
  PasswordVisibilityCubit() : super(true);
}

// inside a widget
onPressed: context.read<PasswordVisibilityCubit>().toggle,

String Extension

SingleValueStringCubitExtension adds an erase() method to any SingleValueCubit<String>, resetting the state to '':

class SearchQueryCubit extends SingleValueCubit<String> {
  SearchQueryCubit() : super('');
}

// inside a widget
onPressed: context.read<SearchQueryCubit>().erase,

Int Extension

SingleValueIntCubitExtension adds increment() and decrement() methods to any SingleValueCubit<int>, stepping the value up or down by 1:

class QuantityCubit extends SingleValueCubit<int> {
  QuantityCubit() : super(1);
}

// inside a widget
IconButton(
  onPressed: context.read<QuantityCubit>().decrement,
  icon: const Icon(Icons.remove),
),
BlocBuilder<QuantityCubit, int>(
  builder: (context, quantity) => Text('$quantity'),
),
IconButton(
  onPressed: context.read<QuantityCubit>().increment,
  icon: const Icon(Icons.add),
),

IntValueCubit

IntValueCubit is a convenience subclass of SingleValueCubit<int> initialized with 0. Use it as a base class whenever the state is a counter or quantity starting from zero:

class CartItemCountCubit extends IntValueCubit {}

TextCubitBinder Example

The TextCubitBinder widget provides two-way binding between a SingleValueCubit<String> and a TextEditingController:

import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:single_value_cubit/single_value_cubit.dart';

class LoginInputCubit extends SingleValueCubit<String> {
  LoginInputCubit() : super('');
}

class MyForm extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return BlocProvider(
      create: (_) => LoginInputCubit(),
      child: Builder(
        builder: (context) {
          return TextCubitBinder(
            cubit: context.read<LoginInputCubit>(),
            builder: (context, controller) {
              return TextField(
                controller: controller,
                decoration: InputDecoration(
                  labelText: 'Login',
                  hintText: 'Enter your login',
                ),
              );
            },
          );
        },
      ),
    );
  }
}

The binding works both ways:

• Changes in the TextField automatically update the cubit state
• Changes to the cubit (e.g., context.read<LoginInputCubit>().set('john_doe')) automatically update the text field