blob: 655203d06dbc767bdbff76bb569ebe8380a82f95 [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 <string>
#include "base/callback.h"
#include "base/compiler_specific.h"
#include "base/containers/hash_tables.h"
#include "base/observer_list.h"
#include "base/prefs/base_prefs_export.h"
#include "base/prefs/pref_notifier.h"
#include "base/prefs/pref_observer.h"
#include "base/threading/thread_checker.h"
class PrefService;
// The PrefNotifier implementation used by the PrefService.
class BASE_PREFS_EXPORT PrefNotifierImpl
: public NON_EXPORTED_BASE(PrefNotifier) {
explicit PrefNotifierImpl(PrefService* pref_service);
virtual ~PrefNotifierImpl();
// If the pref at the given path changes, we call the observer's
// OnPreferenceChanged method.
void AddPrefObserver(const char* path, PrefObserver* observer);
void RemovePrefObserver(const char* path, 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::Callback<void(bool)> observer);
void SetPrefService(PrefService* pref_service);
// PrefNotifier overrides.
virtual void OnPreferenceChanged(const std::string& pref_name) OVERRIDE;
virtual 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 ObserverList<PrefObserver> PrefObserverList;
typedef base::hash_map<std::string, PrefObserverList*> PrefObserverMap;
typedef std::list<base::Callback<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_;
base::ThreadChecker thread_checker_;