chrome/browser/ui/panels/panel_mouse_watcher.h

   1 // Copyright (c) 2012 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_PANELS_PANEL_MOUSE_WATCHER_H_
   6 #define CHROME_BROWSER_UI_PANELS_PANEL_MOUSE_WATCHER_H_
   7
   8 #include "base/gtest_prod_util.h"
   9 #include "base/observer_list.h"
  10
  11 namespace gfx {
  12 class Point;
  13 }
  14
  15 class PanelMouseWatcherObserver;
  16
  17 // This is the base class for functionality to watch for mouse movements.
  18 // The specific implementation of this abstract class differ in how they
  19 // track mouse movements.
  20 class PanelMouseWatcher {
  21  public:
  22   // Returns an instance of the platform specific implementation.
  23   static PanelMouseWatcher* Create();
  24
  25   // clang gives an error asking for an out of line destructor.
  26   virtual ~PanelMouseWatcher();
  27
  28   void AddObserver(PanelMouseWatcherObserver* observer);
  29   void RemoveObserver(PanelMouseWatcherObserver* observer);
  30
  31   // Returns current mouse position. This may be different from the
  32   // mouse position in NotifyMouseMovement.
  33   virtual gfx::Point GetMousePosition() const = 0;
  34
  35  protected:
  36   PanelMouseWatcher();
  37
  38   // |mouse_position| is in screen coordinates.
  39   virtual void NotifyMouseMovement(const gfx::Point& mouse_position);
  40
  41   // Returns true if watching mouse movements.
  42   virtual bool IsActive() const = 0;
  43
  44  private:
  45   friend class PanelMouseWatcherTest;
  46   FRIEND_TEST_ALL_PREFIXES(PanelMouseWatcherTest, StartStopWatching);
  47   friend class BasePanelBrowserTest;
  48
  49   // Start/stop tracking mouse movements.
  50   virtual void Start() = 0;
  51   virtual void Stop() = 0;
  52
  53   base::ObserverList<PanelMouseWatcherObserver> observers_;
  54 };
  55
  56 #endif  // CHROME_BROWSER_UI_PANELS_PANEL_MOUSE_WATCHER_H_