hydrated_riverpod

Description:

hydrated riverpod

hydrated_riverpod #

Overview #
hydrated_riverpod extension to the riverpod state management library which automatically persists and restores riverpod states.
Like hydrated_bloc
hydrated_riverpod exports a Storage interface which means it can work with any storage provider. Out of the box, it comes with its own implementation: HydratedStorage.
HydratedStorage is built on top of hive for a platform-agnostic, performant storage layer.
Usage #
Setup HydratedRiverpod #
void main() async {
WidgetsFlutterBinding.ensureInitialized();
final storage = HydratedStorage.build(storageDirectory: ...)
HydratedRiverpod.initialize(storage: storage);
runApp(ProviderScope(child: MyApp()));
}
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Create a HydratedStateNotifier #
class Counter extends HydratedStateNotifier<int> {
Counter() : super(0);

void increment() => state++;

@override
int fromJson(Map<String, dynamic> json) => json['value'] as int;

@override
Map<String, int> toJson(int state) => { 'value': state };
}
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Now the Counter will automatically persist/restore their state. We can increment the counter value, hot restart, kill the app, etc... and the previous state will be retained.
HydratedMixin #
class Counter extends StateNotifier<int> with HydratedMixin {
CounterCubit() : super(0) {
hydrate();
}

void increment() => state++;

@override
int fromJson(Map<String, dynamic> json) => json['value'] as int;

@override
Map<String, int> toJson(int state) => { 'value': state };
}
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Custom Storage Directory #
Any storageDirectory can be used when creating an instance of HydratedStorage:
final storage = await HydratedStorage.build(
storageDirectory: await getApplicationDocumentsDirectory(),
);
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Custom Hydrated Storage #
If the default HydratedStorage doesn't meet your needs, you can always implement a custom Storage by simply implementing the Storage interface and initializing HydratedRiverpod with the custom Storage.
// my_hydrated_storage.dart

class MyHydratedStorage implements Storage {
@override
dynamic read(String key) {
// TODO: implement read
}

@override
Future<void> write(String key, dynamic value) async {
// TODO: implement write
}

@override
Future<void> delete(String key) async {
// TODO: implement delete
}

@override
Future<void> clear() async {
// TODO: implement clear
}
}
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// main.dart

HydratedRiverpod.initialize(storage: MyHydratedStorage());
runApp(ProviderScope(child: MyApp()));

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Dart Versions #

Dart 2: >= 2.12