Add interface for DesktopMediaPickerModel

chrome/browser/media/desktop_media_picker_model.h

 // Copyright 2013 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_MEDIA_DESKTOP_MEDIA_PICKER_MODEL_H_
 #define CHROME_BROWSER_MEDIA_DESKTOP_MEDIA_PICKER_MODEL_H_
 
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/sequenced_task_runner.h"
 #include "content/public/common/desktop_media_id.h"
 #include "ui/gfx/image/image_skia.h"
 
 namespace webrtc {
 class ScreenCapturer;
 class WindowCapturer;
 }
 
-// DesktopMediaPickerModel provides the list of desktop media source (screens,
-// windows, tabs), and their thumbnails, to the desktop media picker dialog. It
-// transparently updates the list in the background, and notifies the desktop
-// media picker when something changes.
-class DesktopMediaPickerModel {
+// Interface for DesktopMediaPickerModel, which provides the list of desktop
+// media source (screens, windows, tabs), and their thumbnails, to the desktop
+// media picker dialog. It transparently updates the list in the background, and
+// notifies the desktop media picker when something changes.
+class DesktopMediaPickerModelInterface {

[Sergey Ulanov, 2013/09/04 20:39:00]

We don't normally use "Interface" suffix in chromium. Instead it's better to
keep the old name for the interface and then call the implementation
DesktopMediaPickerModelImpl.

[dcaiafa, 2013/09/04 22:41:38]

Done.

  public:
+  virtual ~DesktopMediaPickerModelInterface() {}
+
   // Interface implemented by the picker dialog to receive notifications when
   // the model's contents change.
   class Observer {
    public:
     virtual ~Observer() {}
 
     virtual void OnSourceAdded(int index) = 0;
     virtual void OnSourceRemoved(int index) = 0;
     virtual void OnSourceNameChanged(int index) = 0;
     virtual void OnSourceThumbnailChanged(int index) = 0;
   };
 
   // Struct used to represent each entry in the model.
   struct Source {
     Source(content::DesktopMediaID id, const string16& name);
 
     // Id of the source.
     content::DesktopMediaID id;
 
     // Name of the source that should be shown to the user.
     string16 name;
 
     // The thumbnail for the source.
     gfx::ImageSkia thumbnail;
   };
 
+  // Sets time interval between updates. By default list of sources and their
+  // thumbnail are updated once per second. If called after StartUpdating() then
+  // it will take effect only after the next update.
+  virtual void SetUpdatePeriod(base::TimeDelta period) = 0;
+
+  // Sets size to which the thumbnails should be scaled. If called after
+  // StartUpdating() then some thumbnails may be still scaled to the old size
+  // until they are updated.
+  virtual void SetThumbnailSize(const gfx::Size& thumbnail_size) = 0;
+
+  // Starts updating the model. The model is initially empty, so OnSourceAdded()
+  // notifications will be generated for each existing source as it is
+  // enumerated. After the initial enumeration the model will be refreshed based
+  // on the update period, and notifications generated only for changes in the
+  // model.
+  virtual void StartUpdating(Observer* observer) = 0;
+
+  virtual int source_count() const = 0;
+  virtual const Source& source(int index) const = 0;
+
+ private:
+  DISALLOW_ASSIGN(DesktopMediaPickerModelInterface);
+};
+
+class DesktopMediaPickerModel : public DesktopMediaPickerModelInterface {
+ public:
   // Caller may pass NULL for either of the arguments in case when only some
   // types of sources the model should be populated with (e.g. it will only
   // contain windows, if |screen_capturer| is NULL).
   DesktopMediaPickerModel(scoped_ptr<webrtc::ScreenCapturer> screen_capturer,
                           scoped_ptr<webrtc::WindowCapturer> window_capturer);
   virtual ~DesktopMediaPickerModel();
 
-  // Sets time interval between updates. By default list of sources and their
-  // thumbnail are updated once per second. If called after StartUpdating() then
-  // it will take effect only after the next update.
-  void SetUpdatePeriod(base::TimeDelta period);
-
-  // Sets size to which the thumbnails should be scaled. If called after
-  // StartUpdating() then some thumbnails may be still scaled to the old size
-  // until they are updated.
-  void SetThumbnailSize(const gfx::Size& thumbnail_size);
-
-  // Starts updating the model. The model is initially empty, so OnSourceAdded()
-  // notifications will be generated for each existing source as it is
-  // enumerated. After the initial enumeration the model will be refreshed based
-  // on the update period, and notifications generated only for changes in the
-  // model.
-  void StartUpdating(Observer* observer);
-
-  int source_count() const { return sources_.size(); }
-  const Source& source(int index) const { return sources_.at(index); }
+  // DesktopMediaPickerModelInterface:
+  virtual void SetUpdatePeriod(base::TimeDelta period) OVERRIDE;
+  virtual void SetThumbnailSize(const gfx::Size& thumbnail_size) OVERRIDE;
+  virtual void StartUpdating(Observer* observer) OVERRIDE;
+  virtual int source_count() const OVERRIDE;
+  virtual const Source& source(int index) const OVERRIDE;
 
  private:
   class Worker;
   friend class Worker;
 
   // Struct used to represent sources list the model gets from the Worker.
   struct SourceDescription {
     SourceDescription(content::DesktopMediaID id, const string16& name);
 
     content::DesktopMediaID id;
@@ skipping 38 matching lines @@
 
   // Current list of sources.
   std::vector<Source> sources_;
 
   base::WeakPtrFactory<DesktopMediaPickerModel> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(DesktopMediaPickerModel);
 };
 
 #endif  // CHROME_BROWSER_MEDIA_DESKTOP_MEDIA_PICKER_MODEL_H_