Preliminary interactive layout of window manager's demo_launcher.

The window manager now handles root node resize by resizing its (two) toplevel nodes to match the initial layout. This is just an intermediate step towards generalizing window manager layout a little.

BUGi=393244

Review URL: https://codereview.chromium.org/383123006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@283379 0039d316-1c4b-4281-b951-d872f2087c98

8 files changed, 218 insertions, 45 deletions

diff --git a/mojo/examples/browser/browser.cc b/mojo/examples/browser/browser.cc
index d9fcafa..3f325c3 100644
--- a/mojo/examples/browser/browser.cc
+++ b/mojo/examples/browser/browser.cc
@@ -155,6 +155,8 @@ class Browser : public ApplicationDelegate,
   Browser() : view_manager_(NULL), root_(NULL), widget_(NULL) {}
 
   virtual ~Browser() {
+    if (root_)
+      root_->RemoveObserver(this);
   }
 
  private:
@@ -242,6 +244,7 @@ class Browser : public ApplicationDelegate,
   virtual void OnNodeDestroyed(view_manager::Node* node) OVERRIDE {
     DCHECK_EQ(root_, node);
     node->RemoveObserver(this);
+    root_ = NULL;
   }
 
   scoped_ptr<ViewsInit> views_init_;
diff --git a/mojo/examples/html_viewer/html_document_view.cc b/mojo/examples/html_viewer/html_document_view.cc
index 654161a..becde37 100644
--- a/mojo/examples/html_viewer/html_document_view.cc
+++ b/mojo/examples/html_viewer/html_document_view.cc
@@ -80,6 +80,7 @@ HTMLDocumentView::HTMLDocumentView(ServiceProvider* service_provider,
     : view_manager_(view_manager),
       view_(view_manager::View::Create(view_manager_)),
       web_view_(NULL),
+      root_(NULL),
       repaint_pending_(false),
       navigator_host_(service_provider),
       weak_factory_(this) {
@@ -88,20 +89,23 @@ HTMLDocumentView::HTMLDocumentView(ServiceProvider* service_provider,
 
 HTMLDocumentView::~HTMLDocumentView() {
   view_->RemoveObserver(this);
-
   if (web_view_)
     web_view_->close();
+  if (root_)
+    root_->RemoveObserver(this);
 }
 
 void HTMLDocumentView::AttachToNode(view_manager::Node* node) {
-  node->SetActiveView(view_);
+  root_ = node;
+  root_->SetActiveView(view_);
   view_->SetColor(SK_ColorCYAN);  // Dummy background color.
 
   web_view_ = blink::WebView::create(this);
   ConfigureSettings(web_view_->settings());
   web_view_->setMainFrame(blink::WebLocalFrame::create(this));
+  web_view_->resize(root_->bounds().size());
 
-  web_view_->resize(gfx::Size(node->bounds().size()));
+  root_->AddObserver(this);
 }
 
 void HTMLDocumentView::Load(URLResponsePtr response) {
@@ -184,6 +188,19 @@ void HTMLDocumentView::OnViewInputEvent(view_manager::View* view,
     web_view_->handleInputEvent(*web_event);
 }
 
+void HTMLDocumentView::OnNodeBoundsChanged(view_manager::Node* node,
+                                           const gfx::Rect& old_bounds,
+                                           const gfx::Rect& new_bounds) {
+  DCHECK_EQ(node, root_);
+  web_view_->resize(node->bounds().size());
+}
+
+void HTMLDocumentView::OnNodeDestroyed(view_manager::Node* node) {
+  DCHECK_EQ(node, root_);
+  node->RemoveObserver(this);
+  root_ = NULL;
+}
+
 void HTMLDocumentView::Repaint() {
   repaint_pending_ = false;
 
diff --git a/mojo/examples/html_viewer/html_document_view.h b/mojo/examples/html_viewer/html_document_view.h
index 8c324a5..6d843ab 100644
--- a/mojo/examples/html_viewer/html_document_view.h
+++ b/mojo/examples/html_viewer/html_document_view.h
@@ -9,6 +9,7 @@
 #include "base/memory/weak_ptr.h"
 #include "mojo/public/cpp/application/lazy_interface_ptr.h"
 #include "mojo/public/interfaces/service_provider/service_provider.mojom.h"
+#include "mojo/services/public/cpp/view_manager/node_observer.h"
 #include "mojo/services/public/cpp/view_manager/view_observer.h"
 #include "mojo/services/public/interfaces/navigation/navigation.mojom.h"
 #include "mojo/services/public/interfaces/network/url_loader.mojom.h"
@@ -28,7 +29,8 @@ namespace examples {
 // A view for a single HTML document.
 class HTMLDocumentView : public blink::WebViewClient,
                          public blink::WebFrameClient,
-                         public view_manager::ViewObserver {
+                         public view_manager::ViewObserver,
+                         public view_manager::NodeObserver {
  public:
   HTMLDocumentView(ServiceProvider* service_provider,
                    view_manager::ViewManager* view_manager);
@@ -65,11 +67,18 @@ class HTMLDocumentView : public blink::WebViewClient,
   virtual void OnViewInputEvent(view_manager::View* view,
                                 const EventPtr& event) OVERRIDE;
 
+  // NodeObserver methods:
+  virtual void OnNodeBoundsChanged(view_manager::Node* node,
+                                   const gfx::Rect& old_bounds,
+                                   const gfx::Rect& new_bounds) OVERRIDE;
+  virtual void OnNodeDestroyed(view_manager::Node* node) OVERRIDE;
+
   void Repaint();
 
   view_manager::ViewManager* view_manager_;
   view_manager::View* view_;
   blink::WebView* web_view_;
+  view_manager::Node* root_;
   bool repaint_pending_;
   LazyInterfacePtr<navigation::NavigatorHost> navigator_host_;
 
diff --git a/mojo/examples/media_viewer/media_viewer.cc b/mojo/examples/media_viewer/media_viewer.cc
index 58cb3ed..4221012 100644
--- a/mojo/examples/media_viewer/media_viewer.cc
+++ b/mojo/examples/media_viewer/media_viewer.cc
@@ -14,6 +14,7 @@
 #include "mojo/public/cpp/application/application_impl.h"
 #include "mojo/public/cpp/bindings/interface_impl.h"
 #include "mojo/services/public/cpp/view_manager/node.h"
+#include "mojo/services/public/cpp/view_manager/node_observer.h"
 #include "mojo/services/public/cpp/view_manager/view.h"
 #include "mojo/services/public/cpp/view_manager/view_manager.h"
 #include "mojo/services/public/cpp/view_manager/view_manager_delegate.h"
@@ -202,17 +203,22 @@ class NavigatorImpl : public InterfaceImpl<navigation::Navigator> {
 
 class MediaViewer : public ApplicationDelegate,
                     public view_manager::ViewManagerDelegate,
-                    public ControlPanel::Delegate {
+                    public ControlPanel::Delegate,
+                    public view_manager::NodeObserver {
  public:
   MediaViewer() : app_(NULL),
                   view_manager_(NULL),
+                  root_node_(NULL),
                   control_node_(NULL),
                   content_node_(NULL),
                   control_panel_(this) {
     handler_map_["image/png"] = "mojo:mojo_png_viewer";
   }
 
-  virtual ~MediaViewer() {}
+  virtual ~MediaViewer() {
+    if (root_node_)
+      root_node_->RemoveObserver(this);
+  }
 
   void Navigate(
       uint32_t node_id,
@@ -270,24 +276,32 @@ class MediaViewer : public ApplicationDelegate,
     return true;
   }
 
+  void LayoutNodes() {
+    view_manager::Node* root = content_node_->parent();
+    gfx::Rect control_bounds(root->bounds().width(), 28);
+    control_node_->SetBounds(control_bounds);
+    gfx::Rect content_bounds(0, control_bounds.height(), root->bounds().width(),
+                             root->bounds().height() - control_bounds.height());
+    content_node_->SetBounds(content_bounds);
+  }
+
   // Overridden from view_manager::ViewManagerDelegate:
   virtual void OnRootAdded(view_manager::ViewManager* view_manager,
                            view_manager::Node* root) OVERRIDE {
+    root_node_ = root;
     view_manager_ = view_manager;
 
     control_node_ = view_manager::Node::Create(view_manager_);
-    root->AddChild(control_node_);
-    gfx::Rect control_bounds(root->bounds().width(), 28);
-    control_node_->SetBounds(control_bounds);
-    control_node_->SetActiveView(view_manager::View::Create(view_manager_));
+    root_node_->AddChild(control_node_);
 
+    content_node_ = view_manager::Node::Create(view_manager_);
+    root_node_->AddChild(content_node_);
+
+    control_node_->SetActiveView(view_manager::View::Create(view_manager_));
     control_panel_.Initialize(control_node_);
 
-    content_node_ = view_manager::Node::Create(view_manager_);
-    root->AddChild(content_node_);
-    gfx::Rect content_bounds(0, control_bounds.height(), root->bounds().width(),
-                             root->bounds().height() - control_bounds.height());
-    content_node_->SetBounds(content_bounds);
+    LayoutNodes();
+    root_node_->AddObserver(this);
 
     if (pending_navigate_request_) {
       scoped_ptr<PendingNavigateRequest> request(
@@ -311,7 +325,7 @@ class MediaViewer : public ApplicationDelegate,
         zoomable_media_->ZoomIn();
         break;
       case ControlPanel::CONTROL_ACTUAL_SIZE:
-        zoomable_media_->ZoomToActualSize();
+       zoomable_media_->ZoomToActualSize();
         break;
       case ControlPanel::CONTROL_ZOOM_OUT:
         zoomable_media_->ZoomOut();
@@ -321,6 +335,18 @@ class MediaViewer : public ApplicationDelegate,
     }
   }
 
+  // NodeObserver:
+  virtual void OnNodeBoundsChanged(view_manager::Node* node,
+                                   const gfx::Rect& old_bounds,
+                                   const gfx::Rect& new_bounds) OVERRIDE {
+    LayoutNodes();
+  }
+  virtual void OnNodeDestroyed(view_manager::Node* node) OVERRIDE {
+    DCHECK_EQ(node, root_node_);
+    node->RemoveObserver(this);
+    root_node_ = NULL;
+  }
+
   std::string GetHandlerForContentType(const std::string& content_type) {
     HandlerMap::const_iterator it = handler_map_.find(content_type);
     return it != handler_map_.end() ? it->second : std::string();
@@ -329,6 +355,7 @@ class MediaViewer : public ApplicationDelegate,
   ApplicationImpl* app_;
   scoped_ptr<ViewsInit> views_init_;
   view_manager::ViewManager* view_manager_;
+  view_manager::Node* root_node_;
   view_manager::Node* control_node_;
   view_manager::Node* content_node_;
   ControlPanel control_panel_;
diff --git a/mojo/examples/png_viewer/png_viewer.cc b/mojo/examples/png_viewer/png_viewer.cc
index a6f8741..c9488e7 100644
--- a/mojo/examples/png_viewer/png_viewer.cc
+++ b/mojo/examples/png_viewer/png_viewer.cc
@@ -10,6 +10,7 @@
 #include "mojo/public/cpp/application/application_connection.h"
 #include "mojo/public/cpp/application/application_delegate.h"
 #include "mojo/services/public/cpp/view_manager/node.h"
+#include "mojo/services/public/cpp/view_manager/node_observer.h"
 #include "mojo/services/public/cpp/view_manager/types.h"
 #include "mojo/services/public/cpp/view_manager/view.h"
 #include "mojo/services/public/cpp/view_manager/view_manager.h"
@@ -111,10 +112,17 @@ class NavigatorImpl : public InterfaceImpl<navigation::Navigator> {
 };
 
 class PNGViewer : public ApplicationDelegate,
-                  public view_manager::ViewManagerDelegate {
+                  public view_manager::ViewManagerDelegate,
+                  public view_manager::NodeObserver {
  public:
-  PNGViewer() : content_view_(NULL), zoom_percentage_(kDefaultZoomPercentage) {}
-  virtual ~PNGViewer() {}
+  PNGViewer()
+      : content_view_(NULL),
+        root_(NULL),
+        zoom_percentage_(kDefaultZoomPercentage) {}
+  virtual ~PNGViewer() {
+    if (root_)
+      root_->RemoveObserver(this);
+  }
 
   void UpdateView(view_manager::Id node_id, const SkBitmap& bitmap) {
     bitmap_ = bitmap;
@@ -161,8 +169,10 @@ class PNGViewer : public ApplicationDelegate,
   // Overridden from view_manager::ViewManagerDelegate:
   virtual void OnRootAdded(view_manager::ViewManager* view_manager,
                            view_manager::Node* root) OVERRIDE {
+    root_ = root;
+    root_->AddObserver(this);
     content_view_ = view_manager::View::Create(view_manager);
-    root->SetActiveView(content_view_);
+    root_->SetActiveView(content_view_);
     content_view_->SetColor(SK_ColorGRAY);
     if (!bitmap_.isNull())
       DrawBitmap();
@@ -189,7 +199,21 @@ class PNGViewer : public ApplicationDelegate,
     content_view_->SetContents(skia::GetTopDevice(*canvas)->accessBitmap(true));
   }
 
+  // NodeObserver:
+  virtual void OnNodeBoundsChanged(view_manager::Node* node,
+                                   const gfx::Rect& old_bounds,
+                                   const gfx::Rect& new_bounds) OVERRIDE {
+    DCHECK_EQ(node, root_);
+    DrawBitmap();
+  }
+  virtual void OnNodeDestroyed(view_manager::Node* node) OVERRIDE {
+    DCHECK_EQ(node, root_);
+    node->RemoveObserver(this);
+    root_ = NULL;
+  }
+
   view_manager::View* content_view_;
+  view_manager::Node* root_;
   SkBitmap bitmap_;
   uint16_t zoom_percentage_;
 
diff --git a/mojo/examples/window_manager/window_manager.cc b/mojo/examples/window_manager/window_manager.cc
index b23e908..704c10f 100644
--- a/mojo/examples/window_manager/window_manager.cc
+++ b/mojo/examples/window_manager/window_manager.cc
@@ -24,6 +24,7 @@
 #include "mojo/views/views_init.h"
 #include "ui/events/event.h"
 #include "ui/events/event_constants.h"
+#include "ui/gfx/geometry/size_conversions.h"
 
 #if defined CreateWindow
 #undef CreateWindow
@@ -90,11 +91,14 @@ class NavigatorHost : public InterfaceImpl<navigation::NavigatorHost> {
   DISALLOW_COPY_AND_ASSIGN(NavigatorHost);
 };
 
-class KeyboardManager : public KeyboardClient {
+class KeyboardManager : public KeyboardClient,
+                        public NodeObserver {
  public:
   KeyboardManager() : view_manager_(NULL), node_(NULL) {
   }
   virtual ~KeyboardManager() {
+    if (node_)
+      node_->parent()->RemoveObserver(this);
   }
 
   Node* node() { return node_; }
@@ -110,6 +114,7 @@ class KeyboardManager : public KeyboardClient {
     node_->Embed("mojo:mojo_keyboard");
     application->ConnectToService("mojo:mojo_keyboard", &keyboard_service_);
     keyboard_service_.set_client(this);
+    parent->AddObserver(this);
   }
 
   void Show(Id view_id, const gfx::Rect& bounds) {
@@ -147,6 +152,22 @@ class KeyboardManager : public KeyboardClient {
                                  flags, false)));
   }
 
+  // Overridden from NodeObserver:
+  virtual void OnNodeBoundsChanged(Node* parent,
+                                   const gfx::Rect& old_bounds,
+                                   const gfx::Rect& new_bounds) OVERRIDE {
+    gfx::Rect keyboard_bounds(node_->bounds());
+    keyboard_bounds.set_y(new_bounds.bottom() - keyboard_bounds.height());
+    keyboard_bounds.set_width(keyboard_bounds.width() +
+                              new_bounds.width() - old_bounds.width());
+    node_->SetBounds(keyboard_bounds);
+  }
+  virtual void OnNodeDestroyed(Node* parent) OVERRIDE {
+    DCHECK_EQ(parent, node_->parent());
+    parent->RemoveObserver(this);
+    node_ = NULL;
+  }
+
   KeyboardServicePtr keyboard_service_;
   ViewManager* view_manager_;
 
@@ -158,30 +179,72 @@ class KeyboardManager : public KeyboardClient {
 
 class RootLayoutManager : public NodeObserver {
  public:
-  explicit RootLayoutManager(ViewManager* view_manager,
-                             Node* root,
-                             Id content_node_id)
-                            : root_(root),
-                              view_manager_(view_manager),
-                              content_node_id_(content_node_id) {}
-  virtual ~RootLayoutManager() {}
+  RootLayoutManager(ViewManager* view_manager,
+                    Node* root,
+                    Id content_node_id,
+                    Id launcher_ui_node_id,
+                    Id control_panel_node_id)
+      : root_(root),
+        view_manager_(view_manager),
+        content_node_id_(content_node_id),
+        launcher_ui_node_id_(launcher_ui_node_id),
+        control_panel_node_id_(control_panel_node_id) {}
+  virtual ~RootLayoutManager() {
+    if (root_)
+      root_->RemoveObserver(this);
+  }
 
  private:
   // Overridden from NodeObserver:
   virtual void OnNodeBoundsChanged(Node* node,
-                                   const gfx::Rect& /*old_bounds*/,
+                                   const gfx::Rect& old_bounds,
                                    const gfx::Rect& new_bounds) OVERRIDE {
     DCHECK_EQ(node, root_);
+
     Node* content_node = view_manager_->GetNodeById(content_node_id_);
     content_node->SetBounds(new_bounds);
     // Force the view's bitmap to be recreated
     content_node->active_view()->SetColor(SK_ColorBLUE);
-    // TODO(hansmuller): Do Layout
+
+    int delta_width = new_bounds.width() - old_bounds.width();
+    int delta_height = new_bounds.height() - old_bounds.height();
+
+    Node* launcher_ui_node =
+        view_manager_->GetNodeById(launcher_ui_node_id_);
+    gfx::Rect launcher_ui_bounds(launcher_ui_node->bounds());
+    launcher_ui_bounds.set_width(launcher_ui_bounds.width() + delta_width);
+    launcher_ui_node->SetBounds(launcher_ui_bounds);
+
+    Node* control_panel_node =
+        view_manager_->GetNodeById(control_panel_node_id_);
+    gfx::Rect control_panel_bounds(control_panel_node->bounds());
+    control_panel_bounds.set_x(control_panel_bounds.x() + delta_width);
+    control_panel_node->SetBounds(control_panel_bounds);
+
+    const Node::Children& content_nodes = content_node->children();
+    Node::Children::const_iterator iter = content_nodes.begin();
+    for(; iter != content_nodes.end(); ++iter) {
+      Node* node = *iter;
+      if (node->id() == control_panel_node->id() ||
+          node->id() == launcher_ui_node->id())
+        continue;
+      gfx::Rect node_bounds(node->bounds());
+      node_bounds.set_width(node_bounds.width() + delta_width);
+      node_bounds.set_height(node_bounds.height() + delta_height);
+      node->SetBounds(node_bounds);
+    }
+  }
+  virtual void OnNodeDestroyed(Node* node) OVERRIDE {
+    DCHECK_EQ(node, root_);
+    root_->RemoveObserver(this);
+    root_ = NULL;
   }
 
   Node* root_;
   ViewManager* view_manager_;
-  Id content_node_id_;
+  const Id content_node_id_;
+  const Id launcher_ui_node_id_;
+  const Id control_panel_node_id_;
 
   DISALLOW_COPY_AND_ASSIGN(RootLayoutManager);
 };
@@ -283,16 +346,19 @@ class WindowManager : public ApplicationDelegate,
     node->SetBounds(gfx::Rect(root->bounds().size()));
     content_node_id_ = node->id();
 
-    root_layout_manager_.reset(
-        new RootLayoutManager(view_manager_, root, content_node_id_));
-    root->AddObserver(root_layout_manager_.get());
-
     View* view = View::Create(view_manager_);
     node->SetActiveView(view);
     view->SetColor(SK_ColorBLUE);
 
-    CreateLauncherUI();
-    CreateControlPanel(node);
+    Id launcher_ui_id = CreateLauncherUI();
+    Id control_panel_id = CreateControlPanel(node);
+
+    root_layout_manager_.reset(
+        new RootLayoutManager(view_manager, root,
+                              content_node_id_,
+                              launcher_ui_id,
+                              control_panel_id));
+    root->AddObserver(root_layout_manager_.get());
   }
   virtual void OnViewManagerDisconnected(ViewManager* view_manager) OVERRIDE {
     DCHECK_EQ(view_manager_, view_manager);
@@ -349,7 +415,7 @@ class WindowManager : public ApplicationDelegate,
   }
 
   // TODO(beng): proper layout manager!!
-  void CreateLauncherUI() {
+  Id CreateLauncherUI() {
     navigation::NavigationDetailsPtr nav_details;
     navigation::ResponseDetailsPtr response;
     Node* node = view_manager_->GetNodeById(content_node_id_);
@@ -358,6 +424,7 @@ class WindowManager : public ApplicationDelegate,
     bounds.set_height(kTextfieldHeight);
     launcher_ui_ = CreateChild(content_node_id_, "mojo:mojo_browser", bounds,
                                nav_details.Pass(), response.Pass());
+    return launcher_ui_->id();
   }
 
   void CreateWindow(const std::string& handler_url,
@@ -409,7 +476,7 @@ class WindowManager : public ApplicationDelegate,
         keyboard_manager_->node()->Contains(target->node());
   }
 
-  void CreateControlPanel(view_manager::Node* root) {
+  Id CreateControlPanel(view_manager::Node* root) {
     Node* node = Node::Create(view_manager_);
     View* view = view_manager::View::Create(view_manager_);
     root->AddChild(node);
@@ -424,6 +491,7 @@ class WindowManager : public ApplicationDelegate,
     node->SetBounds(bounds);
 
     debug_panel_ = new DebugPanel(this, node);
+    return node->id();
   }
 
   scoped_ptr<ViewsInit> views_init_;
diff --git a/mojo/views/native_widget_view_manager.cc b/mojo/views/native_widget_view_manager.cc
index 36a6578..1d92e22 100644
--- a/mojo/views/native_widget_view_manager.cc
+++ b/mojo/views/native_widget_view_manager.cc
@@ -90,9 +90,11 @@ class MinimalInputEventFilter : public ui::internal::InputMethodDelegate,
 NativeWidgetViewManager::NativeWidgetViewManager(
     views::internal::NativeWidgetDelegate* delegate, view_manager::Node* node)
     : NativeWidgetAura(delegate),
-      node_(node) {
+      node_(node),
+      view_(node_->active_view()) {
   node_->AddObserver(this);
-  node_->active_view()->AddObserver(this);
+  if (view_)
+    view_->AddObserver(this);
   window_tree_host_.reset(new WindowTreeHostMojo(node_, this));
   window_tree_host_->InitHost();
 
@@ -113,9 +115,10 @@ NativeWidgetViewManager::NativeWidgetViewManager(
 }
 
 NativeWidgetViewManager::~NativeWidgetViewManager() {
-  if (node_->active_view())
-    node_->active_view()->RemoveObserver(this);
-  node_->RemoveObserver(this);
+  if (view_)
+    view_->RemoveObserver(this);
+  if (node_)
+    node_->RemoveObserver(this);
 }
 
 void NativeWidgetViewManager::InitNativeWidget(
@@ -129,13 +132,23 @@ void NativeWidgetViewManager::InitNativeWidget(
 
 void NativeWidgetViewManager::CompositorContentsChanged(
     const SkBitmap& bitmap) {
-  node_->active_view()->SetContents(bitmap);
+  if (view_)
+    view_->SetContents(bitmap);
 }
 
 void NativeWidgetViewManager::OnNodeDestroyed(view_manager::Node* node) {
+  DCHECK_EQ(node, node_);
+  node->RemoveObserver(this);
+  node_ = NULL;
   window_tree_host_.reset();
 }
 
+void NativeWidgetViewManager::OnNodeBoundsChanged(view_manager::Node* node,
+                                                  const gfx::Rect& old_bounds,
+                                                  const gfx::Rect& new_bounds) {
+  GetWidget()->SetBounds(gfx::Rect(node->bounds().size()));
+}
+
 void NativeWidgetViewManager::OnNodeActiveViewChanged(
     view_manager::Node* node,
     view_manager::View* old_view,
@@ -144,6 +157,7 @@ void NativeWidgetViewManager::OnNodeActiveViewChanged(
     old_view->RemoveObserver(this);
   if (new_view)
     new_view->AddObserver(this);
+  view_ = new_view;
 }
 
 void NativeWidgetViewManager::OnViewInputEvent(view_manager::View* view,
@@ -153,4 +167,10 @@ void NativeWidgetViewManager::OnViewInputEvent(view_manager::View* view,
     window_tree_host_->SendEventToProcessor(ui_event.get());
 }
 
+void NativeWidgetViewManager::OnViewDestroyed(view_manager::View* view) {
+  DCHECK_EQ(view, view_);
+  view->RemoveObserver(this);
+  view_ = NULL;
+}
+
 }  // namespace mojo
diff --git a/mojo/views/native_widget_view_manager.h b/mojo/views/native_widget_view_manager.h
index b8050f3..564e467 100644
--- a/mojo/views/native_widget_view_manager.h
+++ b/mojo/views/native_widget_view_manager.h
@@ -47,10 +47,14 @@ class NativeWidgetViewManager : public views::NativeWidgetAura,
   virtual void OnNodeActiveViewChanged(view_manager::Node* node,
                                        view_manager::View* old_view,
                                        view_manager::View* new_view) OVERRIDE;
+  virtual void OnNodeBoundsChanged(view_manager::Node* node,
+                                   const gfx::Rect& old_bounds,
+                                   const gfx::Rect& new_bounds) OVERRIDE;
 
   // view_manager::ViewObserver
   virtual void OnViewInputEvent(view_manager::View* view,
                                 const EventPtr& event) OVERRIDE;
+  virtual void OnViewDestroyed(view_manager::View* view) OVERRIDE;
 
   scoped_ptr<WindowTreeHostMojo> window_tree_host_;
 
@@ -59,6 +63,7 @@ class NativeWidgetViewManager : public views::NativeWidgetAura,
   scoped_ptr<ui::internal::InputMethodDelegate> ime_filter_;
 
   view_manager::Node* node_;
+  view_manager::View* view_;
 
   scoped_ptr<wm::ScopedCaptureClient> capture_client_;