blob: c550103fbc3f1da7bf8178fa574e3f40ce2c62d2 [file] [log] [blame]
// Copyright (c) 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <list>
#include <memory>
#include <string>
#include <unordered_map>
#include "base/callback.h"
#include "base/compiler_specific.h"
#include "base/macros.h"
#include "base/observer_list.h"
#include "base/threading/thread_checker.h"
#include "components/prefs/pref_notifier.h"
#include "components/prefs/pref_observer.h"
#include "components/prefs/prefs_export.h"
class PrefService;
// The PrefNotifier implementation used by the PrefService.
class COMPONENTS_PREFS_EXPORT PrefNotifierImpl : public PrefNotifier {
explicit PrefNotifierImpl(PrefService* pref_service);
~PrefNotifierImpl() override;
// If the pref at the given path changes, we call the observer's
// OnPreferenceChanged method.
void AddPrefObserver(const std::string& path, PrefObserver* observer);
void RemovePrefObserver(const std::string& path, PrefObserver* observer);
// These observers are called for any pref changes.
// AVOID ADDING THESE. See the long comment in the identically-named
// functions on PrefService for background.
void AddPrefObserverAllPrefs(PrefObserver* observer);
void RemovePrefObserverAllPrefs(PrefObserver* observer);
// We run the callback once, when initialization completes. The bool
// parameter will be set to true for successful initialization,
// false for unsuccessful.
void AddInitObserver(base::OnceCallback<void(bool)> observer);
void SetPrefService(PrefService* pref_service);
// PrefNotifier overrides.
void OnPreferenceChanged(const std::string& pref_name) override;
// PrefNotifier overrides.
void OnInitializationCompleted(bool succeeded) override;
// A map from pref names to a list of observers. Observers get fired in the
// order they are added. These should only be accessed externally for unit
// testing.
typedef base::ObserverList<PrefObserver>::Unchecked PrefObserverList;
typedef std::unordered_map<std::string, std::unique_ptr<PrefObserverList>>
typedef std::list<base::OnceCallback<void(bool)>> PrefInitObserverList;
const PrefObserverMap* pref_observers() const { return &pref_observers_; }
// For the given pref_name, fire any observer of the pref. Virtual so it can
// be mocked for unit testing.
virtual void FireObservers(const std::string& path);
// Weak reference; the notifier is owned by the PrefService.
PrefService* pref_service_;
PrefObserverMap pref_observers_;
PrefInitObserverList init_observers_;
// Observers for changes to any preference.
PrefObserverList all_prefs_pref_observers_;
base::ThreadChecker thread_checker_;