distinct_value_connectable_observable 2.0.3+2

Distinct value connectable observable for RxDart, useful for BLoC pattern

distinct_value_connectable_observable

Distinct & Connectable & ValueObservable RxDart

Dart package: https://pub.dartlang.org/packages/distinct_value_connectable_observable.

Useful for flutter BLoC pattern, expose broadcast state stream to UI, can synchronous access to the last emitted item, and distinct until changed

A library for Dart developers. Created from templates made available by Stagehand under a BSD-style license.

Implement BLoC

Without using package	Using package

Usage

A simple usage example:

Import distinct_value_connectable_observable:

import 'package:distinct_value_connectable_observable/distinct_value_connectable_observable.dart';

Wrap your Stream or Observable in a DistinctValueConnectableObservable using constructor:

final Stream<State> state$;
final distinctValueConnectable$ = DistinctValueConnectableObservable(state$);

or

final Stream<State> state$;
final distinctValueConnectable$ = DistinctValueConnectableObservable.seeded(
  state$,
  seedValue: State.initial(),
);

You can pass equals parameter to constructor, used to determined equality:

final Stream<State> state$;
final bool Function(State, State) isEquals;

final distinctValueConnectable$ = DistinctValueConnectableObservable.seeded(
  state$,
  seedValue: State.initial(),
  equals: isEquals,
);

Another approach, using helper functions: publishValueDistinct, publishValueSeededDistinct, shareValueDistinct, shareValueSeededDistinct.

final source = Observable.fromIterable([1, 2, 2, 3, 3, 3]);
final connectable = publishValueDistinct(source);

// Does not print anything at first
connectable.listen(print);

// Start listening to the source Observable. Will cause the previous
// line to start printing 1, 2, 3
final subscription = connectable.connect();

// Late subscribers will receive the last emitted value
connectable.listen(print); // Prints 3

// Can access the latest emitted value synchronously. Prints 3
print(connectable.value);

// Stop emitting items from the source stream and close the underlying
// BehaviorSubject
await subscription.cancel();

Features and bugs

Please file feature requests and bugs at the issue tracker.

License

MIT License

Copyright (c) 2019 Petrus Nguyễn Thái Học

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.