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 CONTENT_BROWSER_HOST_ZOOM_LEVEL_CONTEXT_H_
6 #define CONTENT_BROWSER_HOST_ZOOM_LEVEL_CONTEXT_H_
7 
8 #include <memory>
9 
10 #include "base/macros.h"
11 #include "content/browser/host_zoom_map_impl.h"
12 #include "content/public/browser/browser_thread.h"
13 #include "content/public/browser/zoom_level_delegate.h"
14 
15 namespace content {
16 
17 // This class manages a HostZoomMap and associates it with a ZoomLevelDelegate,
18 // if one is provided. It also serves to keep the zoom level machinery details
19 // separate from the owning StoragePartitionImpl. It must be destroyed on the
20 // UI thread.
21 class HostZoomLevelContext {
22  public:
23   explicit HostZoomLevelContext(
24       std::unique_ptr<ZoomLevelDelegate> zoom_level_delegate);
25 
GetHostZoomMap()26   HostZoomMap* GetHostZoomMap() const { return host_zoom_map_impl_.get(); }
GetZoomLevelDelegate()27   ZoomLevelDelegate* GetZoomLevelDelegate() const {
28     return zoom_level_delegate_.get();
29   }
30 
31  private:
32   friend struct BrowserThread::DeleteOnThread<BrowserThread::UI>;
33   friend class base::DeleteHelper<HostZoomLevelContext>;
34 
35   ~HostZoomLevelContext();
36 
37   std::unique_ptr<HostZoomMapImpl> host_zoom_map_impl_;
38   // Release the delegate before the HostZoomMap, in case it is carrying
39   // any HostZoomMap::Subscription pointers.
40   std::unique_ptr<ZoomLevelDelegate> zoom_level_delegate_;
41 
42   DISALLOW_COPY_AND_ASSIGN(HostZoomLevelContext);
43 };
44 
45 }  // namespace content
46 
47 #endif  // CONTENT_BROWSER_HOST_ZOOM_LEVEL_CONTEXT_H_
48