aura: Draw drop shadows under browsers and menus.

ui/aura/window.h

 // Copyright (c) 2011 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_WINDOW_H_
 #define UI_AURA_WINDOW_H_
 #pragma once
 
 #include <map>
 #include <vector>
@@ skipping 28 matching lines @@
 class KeyEvent;
 class LayoutManager;
 class MouseEvent;
 class ToplevelWindowContainer;
 class TouchEvent;
 class WindowDelegate;
 class WindowObserver;
 
 namespace internal {
 class FocusManager;
+class Shadow;
 }
 
 // Aura window implementation. Interesting events are sent to the
 // WindowDelegate.
 // TODO(beng): resolve ownership.
 class AURA_EXPORT Window : public ui::LayerDelegate {
  public:
   typedef std::vector<Window*> Windows;
 
   explicit Window(WindowDelegate* delegate);
@@ skipping 24 matching lines @@
   const gfx::Rect& bounds() const;
   const gfx::Rect& restore_bounds() const { return restore_bounds_; }
 
   Window* parent() { return parent_; }
   const Window* parent() const { return parent_; }
 
   // The Window does not own this object.
   void set_user_data(void* user_data) { user_data_ = user_data; }
   void* user_data() const { return user_data_; }
 
+  // Just made available for tests; outside callers shouldn't need to modify it.
+  const internal::Shadow* shadow() const { return shadow_.get(); }
+
   // Changes the visibility of the window.
   void Show();
   void Hide();
   // Returns true if this window and all its ancestors are visible.
   bool IsVisible() const;
 
   // Returns the window's bounds in screen coordinates.
   gfx::Rect GetScreenBounds() const;
 
   // Activates this window. Only top level windows can be activated. Requests
@@ skipping 155 matching lines @@
   void SetIntProperty(const char* name, int value);
 
   // Returns the window property for given |name|.  Returns NULL or 0 if
   // the property does not exist.
   // TODO(oshima): Returning 0 for non existing property is problematic.
   // Fix ViewProp to be able to tell if the property exists and
   // change it to -1.
   void* GetProperty(const char* name) const;
   int GetIntProperty(const char* name) const;
 
+  // Sets whether a drop shadow should be displayed around this window or not.
+  // By default, shadows aren't displayed.  It's safe to call this method before
+  // calling Init().
+  void SetShadowVisible(bool visible);
+
  protected:
   // Returns the desktop or NULL if we aren't yet attached to a desktop.
   virtual Desktop* GetDesktop();
 
   // Called when the |window| is detached from the desktop by being
   // removed from its parent.
   virtual void WindowDetachedFromDesktop(aura::Window* window);
 
  private:
   friend class LayoutManager;
@@ skipping 15 matching lines @@
   // Gets a Window (either this one or a subwindow) containing |local_point|.
   // If |return_tightest| is true, returns the tightest-containing (i.e.
   // furthest down the hierarchy) Window containing the point; otherwise,
   // returns the loosest.  If |for_event_handling| is true, then hit-test masks
   // and StopsEventPropagation() are honored; otherwise, only bounds checks are
   // performed.
   Window* GetWindowForPoint(const gfx::Point& local_point,
                             bool return_tightest,
                             bool for_event_handling);
 
+  // Initialize |shadow_|.  Init() must be called first.
+  void InitShadow();
+
   // Overridden from ui::LayerDelegate:
   virtual void OnPaintLayer(gfx::Canvas* canvas) OVERRIDE;
 
   WindowType type_;
 
   WindowDelegate* delegate_;
 
   // The original bounds of a maximized/fullscreen window.
   gfx::Rect restore_bounds_;
 
@@ skipping 29 matching lines @@
 
   ObserverList<WindowObserver> observers_;
 
   // We're using ViewProp to store the property (for now) instead of
   // just using std::map because chrome is still using |ViewProp| class
   // to create and access property.
   // TODO(oshima): Consolidcate ViewProp and aura::window property
   // implementation.
   std::map<const char*, void*> prop_map_;
 
+  // NULL if SetShadowVisible(true) has never been called.
+  scoped_ptr<internal::Shadow> shadow_;

[sky, 2011/11/15 04:49:13]

Would it work to make the shadow a transient child that is stacked below rather
than above the window?

+
+  // Is |shadow_| currently being shown?
+  bool show_shadow_;
+
   DISALLOW_COPY_AND_ASSIGN(Window);
 };
 
 }  // namespace aura
 
 #endif  // UI_AURA_WINDOW_H_