Zoom Extension API

chrome/browser/ui/zoom/zoom_controller.h

 // 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.
 
 #ifndef CHROME_BROWSER_UI_ZOOM_ZOOM_CONTROLLER_H_
 #define CHROME_BROWSER_UI_ZOOM_ZOOM_CONTROLLER_H_
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/prefs/pref_member.h"
 #include "content/public/browser/host_zoom_map.h"
 #include "content/public/browser/web_contents_observer.h"
 #include "content/public/browser/web_contents_user_data.h"
+#include "extensions/common/extension.h"
 
 class ZoomObserver;
 
 namespace content {
 class WebContents;
 }
 
 // Per-tab class to manage the Omnibox zoom icon.
 class ZoomController : public content::WebContentsObserver,
                        public content::WebContentsUserData<ZoomController> {
  public:
   virtual ~ZoomController();
 
   int zoom_percent() const { return zoom_percent_; }
 
   // Convenience method to quickly check if the tab's at default zoom.
   bool IsAtDefaultZoom() const;
 
   // Returns which image should be loaded for the current zoom level.
   int GetResourceForZoomLevel() const;
 
+  // Gets an extensoin from |zoom_extension_map_| by zoom ID.
+  const extensions::Extension* GetExtensionById(int zoom_id) const;
+
+  int last_zoom_id() const;
+
   void set_observer(ZoomObserver* observer) { observer_ = observer; }
 
+  // Sets the zoom level through WebContents::SetZoomLevel(), associates
+  // |extension| with that zoom change's zoom ID, and returns the zoom ID.
+  int SetZoomLevelByExtension(
+      double zoom_level,
+      scoped_refptr<const extensions::Extension> extension);
+
   // content::WebContentsObserver overrides:
   virtual void DidNavigateMainFrame(
       const content::LoadCommittedDetails& details,
       const content::FrameNavigateParams& params) OVERRIDE;
 
  private:
   explicit ZoomController(content::WebContents* web_contents);
   friend class content::WebContentsUserData<ZoomController>;
   friend class ZoomControllerTest;
 
   void OnZoomLevelChanged(const content::HostZoomMap::ZoomLevelChange& change);
 
   // Updates the zoom icon and zoom percentage based on current values and
   // notifies the observer if changes have occurred. |host| may be empty,
   // meaning the change should apply to ~all sites. If it is not empty, the
   // change only affects sites with the given host.
   void UpdateState(const std::string& host);
+  void UpdateState(const std::string& host, int zoom_id,
+                   bool is_temporary_zoom);
 
   // The current zoom percentage.
   int zoom_percent_;
 
   // Used to access the default zoom level preference.
   DoublePrefMember default_zoom_level_;
 
+  // Used to keep track of which extensions initiated which zoom changes.
+  typedef std::map<int, scoped_refptr<
+                          const extensions::Extension> > ZoomExtensionMap;
+  ZoomExtensionMap zoom_extension_map_;
+
+  // Keeps track of the zoom_id of the last zoom change that took effect.
+  int last_zoom_id_;
+
   // Observer receiving notifications on state changes.
   ZoomObserver* observer_;
 
   content::BrowserContext* browser_context_;
 
   scoped_ptr<content::HostZoomMap::Subscription> zoom_subscription_;
 
   DISALLOW_COPY_AND_ASSIGN(ZoomController);
 };
 
 #endif  // CHROME_BROWSER_UI_ZOOM_ZOOM_CONTROLLER_H_