| // Copyright (c) 2015, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| import 'dart:async'; |
| |
| import '../typed/stream_subscription.dart'; |
| |
| /// Simple delegating wrapper around a [StreamSubscription]. |
| /// |
| /// Subclasses can override individual methods. |
| class DelegatingStreamSubscription<T> implements StreamSubscription<T> { |
| final StreamSubscription<T> _source; |
| |
| /// Create delegating subscription forwarding calls to [sourceSubscription]. |
| DelegatingStreamSubscription(StreamSubscription<T> sourceSubscription) |
| : _source = sourceSubscription; |
| |
| /// Creates a wrapper which throws if [subscription]'s events aren't instances |
| /// of `T`. |
| /// |
| /// This soundly converts a [StreamSubscription] to a `StreamSubscription<T>`, |
| /// regardless of its original generic type, by asserting that its events are |
| /// instances of `T` whenever they're provided. If they're not, the |
| /// subscription throws a [CastError]. |
| @Deprecated('Use Stream.cast instead') |
| // TODO - Remove `TypeSafeStreamSubscription` and tests when removing this. |
| static StreamSubscription<T> typed<T>(StreamSubscription subscription) => |
| subscription is StreamSubscription<T> |
| ? subscription |
| : TypeSafeStreamSubscription<T>(subscription); |
| |
| @override |
| void onData(void Function(T)? handleData) { |
| _source.onData(handleData); |
| } |
| |
| @override |
| void onError(Function? handleError) { |
| _source.onError(handleError); |
| } |
| |
| @override |
| void onDone(void Function()? handleDone) { |
| _source.onDone(handleDone); |
| } |
| |
| @override |
| void pause([Future? resumeFuture]) { |
| _source.pause(resumeFuture); |
| } |
| |
| @override |
| void resume() { |
| _source.resume(); |
| } |
| |
| @override |
| Future cancel() => _source.cancel(); |
| |
| @override |
| Future<E> asFuture<E>([E? futureValue]) => _source.asFuture(futureValue); |
| |
| @override |
| bool get isPaused => _source.isPaused; |
| } |