Adds View::visible() and IsDrawn

mojo/services/public/cpp/view_manager/view.h

 // Copyright 2014 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 MOJO_SERVICES_PUBLIC_CPP_VIEW_MANAGER_VIEW_H_
 #define MOJO_SERVICES_PUBLIC_CPP_VIEW_MANAGER_VIEW_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
@@ skipping 28 matching lines @@
 
   // Destroys this view and all its children.
   void Destroy();
 
   ViewManager* view_manager() { return manager_; }
 
   // Configuration.
   Id id() const { return id_; }
 
   // Geometric disposition.
-  const gfx::Rect& bounds() { return bounds_; }
+  const gfx::Rect& bounds() const { return bounds_; }
   void SetBounds(const gfx::Rect& bounds);
 
-  // Visibility.
+  // Visibility (also see IsDrawn()).
+  bool visible() const { return visible_; }
   void SetVisible(bool value);
-  // TODO(sky): add accessor.
+
+  // A View is drawn if the View and all its ancestors are visible and the
+  // View is attached to the root.
+  bool IsDrawn() const;
 
   // Observation.
   void AddObserver(ViewObserver* observer);
   void RemoveObserver(ViewObserver* observer);
 
   // Tree.
   View* parent() { return parent_; }
   const View* parent() const { return parent_; }
   const Children& children() const { return children_; }
 
@@ skipping 33 matching lines @@
   friend class ViewManagerClientImpl;
 
   explicit View(ViewManager* manager);
 
   void LocalDestroy();
   void LocalAddChild(View* child);
   void LocalRemoveChild(View* child);
   // Returns true if the order actually changed.
   bool LocalReorder(View* relative, OrderDirection direction);
   void LocalSetBounds(const gfx::Rect& old_bounds, const gfx::Rect& new_bounds);
+  void LocalSetDrawn(bool drawn);
   void CreateBitmapUploader();
 
   ViewManager* manager_;
   Id id_;
   View* parent_;
   Children children_;
 
   ObserverList<ViewObserver> observers_;
 
   gfx::Rect bounds_;
+
+  bool visible_;
+
+  // Drawn state is derived from the visible state and the parent's visible
+  // state. This field is only used if the view has no parent (eg it's a root).
+  bool drawn_;
+
   // TODO(jamesr): Temporary, remove when all clients are using surfaces
   // directly.
   scoped_ptr<BitmapUploader> bitmap_uploader_;
 
   DISALLOW_COPY_AND_ASSIGN(View);
 };
 
 }  // namespace mojo
 
 #endif  // MOJO_SERVICES_PUBLIC_CPP_VIEW_MANAGER_VIEW_H_