blob: 8f785420492d8605794a52e4d65ac4eef0ea27bb [file] [log] [blame]
// Copyright (c) 2012 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 <vector>
#include "base/macros.h"
#include "base/sequence_checker.h"
#include "content/common/content_export.h"
namespace content {
class NotificationObserver;
class NotificationSource;
// Aids in registering for notifications and ensures that all registered
// notifications are unregistered when the class is destroyed.
// The intended use is that you make a NotificationRegistrar member in your
// class and use it to register your notifications instead of going through the
// notification service directly. It will automatically unregister them for
// you.
class CONTENT_EXPORT NotificationRegistrar {
// This class must not be derived from (we don't have a virtual destructor so
// it won't work). Instead, use it as a member in your class.
// Wrappers around NotificationService::[Add|Remove]Observer.
void Add(NotificationObserver* observer,
int type,
const NotificationSource& source);
void Remove(NotificationObserver* observer,
int type,
const NotificationSource& source);
// Unregisters all notifications.
void RemoveAll();
// Returns true if no notifications are registered.
bool IsEmpty() const;
// Returns true if there is already a registered notification with the
// specified details.
bool IsRegistered(NotificationObserver* observer,
int type,
const NotificationSource& source);
struct Record;
// We keep registered notifications in a simple vector. This means we'll do
// brute-force searches when removing them individually, but individual
// removal is uncommon, and there will typically only be a couple of
// notifications anyway.
typedef std::vector<Record> RecordVector;
// Lists all notifications we're currently registered for.
RecordVector registered_;
} // namespace content