| // Copyright 2018 The Fuchsia Authors. 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 'change.dart'; |
| import 'value.dart'; |
| import 'value_observer.dart'; |
| |
| /// Interface implemented by all observable Sledge Values. |
| /// See the documentation for the `Value` class for a description |
| /// of its role. |
| abstract class LeafValue implements Value { |
| /// Observes events occurring on this value. |
| set observer(ValueObserver observer); |
| |
| /// Ends the transaction and retrieves its data. |
| Change getChange(); |
| |
| /// Applies external transactions. |
| void applyChange(Change input); |
| |
| /// Rolls back all local modifications. |
| void rollbackChange(); |
| |
| /// Ends the transaction in progress and deletes the rollback data. |
| void completeTransaction(); |
| |
| /// The Stream of changes. |
| Stream<Object> get onChange; |
| } |
