riverpod_hook_mutation 0.0.3

A package that provides a simple way to manage mutations in Riverpod

example/lib/main.dart

import 'dart:math';

import 'package:flutter/material.dart';
import 'package:hooks_riverpod/hooks_riverpod.dart';
import 'package:riverpod_annotation/riverpod_annotation.dart';
import 'package:riverpod_hook_mutation/riverpod_hook_mutation.dart';

part 'main.g.dart';

void main(List<String> args) {
  runApp(
    const ProviderScope(
      child: MaterialApp(home: ExampleScreen()),
    ),
  );
}

class Repository {
  static final Repository _instance = Repository._internal();

  factory Repository() => _instance;

  Repository._internal();

  final _todos = [
    TODO(
      title: 'Buy milk',
      completed: false,
    ),
    TODO(
      title: 'Buy eggs',
      completed: true,
    ),
    TODO(
      title: 'Buy bread',
      completed: false,
    ),
  ];

  Future<List<TODO>> fetchTodos() async {
    await Future.delayed(const Duration(seconds: 1));
    return _todos;
  }

  Future<TODO> createTodo() async {
    return Future.delayed(const Duration(seconds: 5), () {
      final todo = TODO(
        title: 'Buy cheese ${Random().nextInt(1000000)}',
        completed: false,
      );
      _todos.add(todo);
      return todo;
    });
  }
}

class TODO {
  final String title;
  final bool completed;

  TODO({
    required this.title,
    required this.completed,
  });
}

@riverpod
class Example extends _$Example {
  @override
  Future<List<TODO>> build() {
    return Repository().fetchTodos();
  }

  Future<TODO> addTodo() async {
    final result = await Repository().createTodo();
    ref.invalidateSelf();
    return result;
  }
}

class ExampleScreen extends HookConsumerWidget {
  const ExampleScreen({super.key});

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final provider = exampleProvider;
    final todos = ref.watch(provider);

    return Scaffold(
      appBar: AppBar(
        actions: [
          FloatingActionButton.small(
            child: const Icon(Icons.add),
            onPressed: () {
              Navigator.of(context).push(
                MaterialPageRoute(
                  builder: (_) {
                    return const AddScreen();
                  },
                ),
              );
            },
          )
        ],
      ),
      body: todos.when(
        data: (data) {
          return RefreshIndicator(
            onRefresh: () => ref.read(provider.future),
            child: ListView.builder(
              itemCount: data.length,
              itemBuilder: (context, index) {
                final todo = data[index];
                return ListTile(
                  title: Text(todo.title),
                );
              },
            ),
          );
        },
        error: (error, stackTrace) {
          return Center(
            child: Text('Error: $error'),
          );
        },
        loading: () {
          return const Center(
            child: CircularProgressIndicator(),
          );
        },
      ),
    );
  }
}

class AddScreen extends HookConsumerWidget {
  const AddScreen({super.key});

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final addTodo = useMutation<TODO>();

    return Scaffold(
      appBar: AppBar(
        actions: [
          FloatingActionButton.small(
            child: addTodo.when(
              idle: () {
                return const Icon(Icons.add);
              },
              data: (data) {
                return const Icon(Icons.add);
              },
              error: (error, stackTrace) {
                return const Icon(Icons.add_circle_outline);
              },
              loading: CircularProgressIndicator.new,
            ),
            onPressed: () {
              final notifier = ref.read(exampleProvider.notifier);

              addTodo.future(
                notifier.addTodo(),
                data: (data) {
                  ScaffoldMessenger.of(context).showSnackBar(
                    SnackBar(
                      content: Text('Created todo: ${data.title}'),
                    ),
                  );
                },
                error: (error, stackTrace) {
                  ScaffoldMessenger.of(context).showSnackBar(
                    SnackBar(
                      content: Text('Failed to create todo: $error'),
                    ),
                  );
                },
              );
            },
          ),
        ],
      ),
    );
  }
}