text: // 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_WM_PUBLIC_ACTIVATION_CLIENT_H_
  #define UI_WM_PUBLIC_ACTIVATION_CLIENT_H_
  
  #include "ui/aura/aura_export.h"
  
  namespace aura {
  class Window;
  
  namespace client {
  class ActivationChangeObserver;
  
  // An interface implemented by an object that manages window activation.
  class AURA_EXPORT ActivationClient {
   public:
    // Adds/Removes ActivationChangeObservers.
    virtual void AddObserver(ActivationChangeObserver* observer) = 0;
    virtual void RemoveObserver(ActivationChangeObserver* observer) = 0;
  
    // Activates |window|. If |window| is NULL, nothing happens.
    virtual void ActivateWindow(Window* window) = 0;
  
    // Deactivates |window|. What (if anything) is activated next is up to the
    // client. If |window| is NULL, nothing happens.
    virtual void DeactivateWindow(Window* window) = 0;
  
    // Retrieves the active window, or NULL if there is none.
    virtual Window* GetActiveWindow() = 0;
  
    // Retrieves the activatable window for |window|, or NULL if there is none.
    // Note that this is often but not always the toplevel window (see
    // GetToplevelWindow() below), as the toplevel window may not be activatable
    // (for example it may be blocked by a modal transient, or some other
    // condition).
    virtual Window* GetActivatableWindow(Window* window) = 0;
  
    // Retrieves the toplevel window for |window|, or NULL if there is none.
    virtual Window* GetToplevelWindow(Window* window) = 0;
  
    // Returns true if |window| can be activated, false otherwise. If |window| has
    // a modal child it can not be activated.
    virtual bool CanActivateWindow(Window* window) const = 0;
  
   protected:
    virtual ~ActivationClient() {}
  };
  
  // Sets/Gets the activation client on the root Window.
  AURA_EXPORT void SetActivationClient(Window* root_window,
                                       ActivationClient* client);
  AURA_EXPORT ActivationClient* GetActivationClient(Window* root_window);
  
  // Some types of transient window are only visible when active.
  // The transient parents of these windows may have visual appearance properties
  // that differ from transient parents that can be deactivated.
  // The presence of this property implies these traits.
  // TODO(beng): currently the UI framework (views) implements the actual
  //             close-on-deactivate component of this feature but it should be
  //             possible to implement in the aura client.
  AURA_EXPORT void SetHideOnDeactivate(Window* window, bool hide_on_deactivate);
  AURA_EXPORT bool GetHideOnDeactivate(Window* window);
  
  }  // namespace clients
  }  // namespace aura
  
  #endif  // UI_WM_PUBLIC_ACTIVATION_CLIENT_H_
  