1// Copyright 2014 The Chromium Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style license that can be 3// found in the LICENSE file. 4 5#ifndef CHROME_BROWSER_UI_ZOOM_ZOOM_EVENT_MANAGER_H_ 6#define CHROME_BROWSER_UI_ZOOM_ZOOM_EVENT_MANAGER_H_ 7 8#include "base/callback_list.h" 9#include "base/supports_user_data.h" 10#include "content/public/browser/host_zoom_map.h" 11 12namespace content { 13class BrowserContext; 14} // namespace content 15 16// This class serves as a target for event notifications from all ZoomController 17// objects. Classes that need to know about browser-specific zoom events (e.g. 18// manual-mode zoom) should subscribe here. 19class ZoomEventManager : public base::SupportsUserData::Data { 20 public: 21 ZoomEventManager(); 22 virtual ~ZoomEventManager(); 23 24 // Returns the ZoomEventManager for the specified BrowserContext. This 25 // function creates the ZoomEventManager if it hasn't been created already. 26 static ZoomEventManager* GetForBrowserContext( 27 content::BrowserContext* context); 28 29 // Called by ZoomControllers when changes are made to zoom levels in manual 30 // mode in order that browser listeners can be notified. 31 void OnZoomLevelChanged(const content::HostZoomMap::ZoomLevelChange& change); 32 33 // Add and remove zoom level changed callbacks. 34 scoped_ptr<content::HostZoomMap::Subscription> AddZoomLevelChangedCallback( 35 const content::HostZoomMap::ZoomLevelChangedCallback& callback); 36 37 private: 38 base::CallbackList<void(const content::HostZoomMap::ZoomLevelChange&)> 39 zoom_level_changed_callbacks_; 40 41 DISALLOW_COPY_AND_ASSIGN(ZoomEventManager); 42}; 43 44#endif // CHROME_BROWSER_UI_ZOOM_ZOOM_EVENT_MANAGER_H_ 45