Notify child widgets before and after a reparenting.

Attaching a native view to a NativeViewHostWin may cause that
view to be disassociated from a view hierarchy with a different
FocusManager.  Notifying the widgets that they are about to be
removed from their current parent gives them the opportunity to
disassociate themselves from their current FocusManager.

BUG=77447
TEST=none


Review URL: http://codereview.chromium.org/6776025

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@80096 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 40 insertions, 21 deletions

diff --git a/views/controls/native/native_view_host_win.cc b/views/controls/native/native_view_host_win.cc
index f8bda8e..f25e722 100644
--- a/views/controls/native/native_view_host_win.cc
+++ b/views/controls/native/native_view_host_win.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -35,33 +35,15 @@ void NativeViewHostWin::NativeViewAttached() {
   // borders), when we change the parent below.
   ShowWindow(host_->native_view(), SW_HIDE);
 
-  // Need to set the HWND's parent before changing its size to avoid flashing.
-  SetParent(host_->native_view(), host_->GetWidget()->GetNativeView());
+  NativeWidget::ReparentNativeView(host_->native_view(),
+                                   host_->GetWidget()->GetNativeView());
   host_->Layout();
-  // Notify children that parent changed, so they can adjust focus.
-  NativeWidget::NativeWidgets widgets;
-  NativeWidget::GetAllNativeWidgets(host_->native_view(), &widgets);
-  for (NativeWidget::NativeWidgets::iterator it = widgets.begin();
-       it != widgets.end(); ++it) {
-    (*it)->GetWidget()->NotifyNativeViewHierarchyChanged(
-        true,
-        host_->GetWidget()->GetNativeView());
-  }
 }
 
 void NativeViewHostWin::NativeViewDetaching(bool destroyed) {
   if (!destroyed && installed_clip_)
     UninstallClip();
   installed_clip_ = false;
-  // Notify children that parent is removed.
-  NativeWidget::NativeWidgets widgets;
-  NativeWidget::GetAllNativeWidgets(host_->native_view(), &widgets);
-  for (NativeWidget::NativeWidgets::iterator it = widgets.begin();
-       it != widgets.end(); ++it) {
-    (*it)->GetWidget()->NotifyNativeViewHierarchyChanged(
-        false,
-        host_->GetWidget()->GetNativeView());
-  }
 }
 
 void NativeViewHostWin::AddedToWidget() {
diff --git a/views/widget/native_widget.h b/views/widget/native_widget.h
index 089cfb3..9b28ac7 100644
--- a/views/widget/native_widget.h
+++ b/views/widget/native_widget.h
@@ -52,6 +52,11 @@ class NativeWidget {
   static void GetAllNativeWidgets(gfx::NativeView native_view,
                                   NativeWidgets* children);
 
+  // Reparent a NativeView and notify all NativeWidgets in
+  // |native_view|'s hierarchy of the change.
+  static void ReparentNativeView(gfx::NativeView native_view,
+                                 gfx::NativeView new_parent);
+
   // Returns the Widget associated with this NativeWidget. This function is
   // guaranteed to return non-NULL for the lifetime of the NativeWidget.
   virtual Widget* GetWidget() = 0;
diff --git a/views/widget/widget_win.cc b/views/widget/widget_win.cc
index 613ddb6..0d6f47c 100644
--- a/views/widget/widget_win.cc
+++ b/views/widget/widget_win.cc
@@ -1150,4 +1150,36 @@ void NativeWidget::GetAllNativeWidgets(gfx::NativeView native_view,
       reinterpret_cast<LPARAM>(children));
 }
 
+void NativeWidget::ReparentNativeView(gfx::NativeView native_view,
+                                      gfx::NativeView new_parent) {
+  if (!native_view)
+    return;
+
+  HWND previous_parent = ::GetParent(native_view);
+  if (previous_parent == new_parent)
+    return;
+
+  NativeWidgets widgets;
+  GetAllNativeWidgets(native_view, &widgets);
+
+  // First notify all the widgets that they are being disassociated
+  // from their previous parent.
+  for (NativeWidgets::iterator it = widgets.begin();
+       it != widgets.end(); ++it) {
+    // TODO(beng): Rename this notification to NotifyNativeViewChanging()
+    // and eliminate the bool parameter.
+    (*it)->GetWidget()->NotifyNativeViewHierarchyChanged(false,
+                                                         previous_parent);
+  }
+
+  ::SetParent(native_view, new_parent);
+
+  // And now, notify them that they have a brand new parent.
+  for (NativeWidgets::iterator it = widgets.begin();
+       it != widgets.end(); ++it) {
+    (*it)->GetWidget()->NotifyNativeViewHierarchyChanged(true,
+                                                         new_parent);
+  }
+}
+
 }  // namespace views