ui/aura/window_tracker.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 UI_AURA_WINDOW_TRACKER_H_
   6 #define UI_AURA_WINDOW_TRACKER_H_
   7
   8 #include <set>
   9
  10 #include "base/basictypes.h"
  11 #include "base/compiler_specific.h"
  12 #include "ui/aura/aura_export.h"
  13 #include "ui/aura/window_observer.h"
  14
  15 namespace aura {
  16
  17 // This class keeps track of a set of windows. A Window is removed either
  18 // explicitly by Remove(), or implicitly when the window is destroyed.
  19 class AURA_EXPORT WindowTracker : public WindowObserver {
  20  public:
  21   typedef std::set<Window*> Windows;
  22
  23   WindowTracker();
  24   ~WindowTracker() override;
  25
  26   // Returns the set of windows being observed.
  27   const std::set<Window*>& windows() const { return windows_; }
  28
  29   // Adds |window| to the set of Windows being tracked.
  30   void Add(Window* window);
  31
  32   // Removes |window| from the set of windows being tracked.
  33   void Remove(Window* window);
  34
  35   // Returns true if |window| was previously added and has not been removed or
  36   // deleted.
  37   bool Contains(Window* window);
  38
  39   // WindowObserver overrides:
  40   void OnWindowDestroying(Window* window) override;
  41
  42  private:
  43   Windows windows_;
  44
  45   DISALLOW_COPY_AND_ASSIGN(WindowTracker);
  46 };
  47
  48 }  // namespace aura
  49
  50 #endif  // UI_AURA_WINDOW_TRACKER_H_