1 files changed, 45 insertions, 0 deletions
diff --git a/ui/aura/env.h b/ui/aura/env.h
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index 0000000..12cb2ef
--- /dev/null
+++ b/ui/aura/env.h
@@ -0,0 +1,45 @@
+// 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 UI_AURA_ENV_H_
+#define UI_AURA_ENV_H_
+#pragma once
+
+#include "base/observer_list.h"
+#include "ui/aura/aura_export.h"
+
+namespace aura {
+
+class EnvObserver;
+class Window;
+
+// A singleton object that tracks general state within Aura.
+// TODO(beng): manage RootWindows.
+class AURA_EXPORT Env {
+ public:
+  Env();
+  ~Env();
+
+  static Env* GetInstance();
+  static void DeleteInstance();
+
+  void AddObserver(EnvObserver* observer);
+  void RemoveObserver(EnvObserver* observer);
+
+ private:
+  friend class Window;
+
+  // Called by the Window when it is initialized. Notifies observers.
+  void NotifyWindowInitialized(Window* window);
+
+  ObserverList<EnvObserver> observers_;
+
+  static Env* instance_;
+
+  DISALLOW_COPY_AND_ASSIGN(Env);
+};
+
+}  // namespace aura
+
+#endif  // UI_AURA_ENV_H_