Browser should get notified if a views textfield changes focus. In addition,

chrome/browser/ui/touch/frame/touch_browser_frame_view.cc

 // Copyright (c) 2010 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.
 
 #include "chrome/browser/ui/touch/frame/touch_browser_frame_view.h"
 
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/renderer_host/render_view_host.h"
 #include "chrome/browser/tab_contents/navigation_controller.h"
 #include "chrome/browser/tab_contents/tab_contents.h"
@@ skipping 17 matching lines @@
 
 }  // namespace
 
 ///////////////////////////////////////////////////////////////////////////////
 // TouchBrowserFrameView, public:
 
 TouchBrowserFrameView::TouchBrowserFrameView(BrowserFrame* frame,
                                              BrowserView* browser_view)
     : OpaqueBrowserFrameView(frame, browser_view),
       keyboard_showing_(false),
-      keyboard_(NULL) {
+      keyboard_(NULL),
+      focus_listener_added_(false) {
   registrar_.Add(this,
                  NotificationType::NAV_ENTRY_COMMITTED,
                  NotificationService::AllSources());
   registrar_.Add(this,
                  NotificationType::FOCUS_CHANGED_IN_PAGE,
                  NotificationService::AllSources());
   registrar_.Add(this,
                  NotificationType::TAB_CONTENTS_DESTROYED,
                  NotificationService::AllSources());
 
   browser_view->browser()->tabstrip_model()->AddObserver(this);
 }
 
 TouchBrowserFrameView::~TouchBrowserFrameView() {
   browser_view()->browser()->tabstrip_model()->RemoveObserver(this);
 }
 
 void TouchBrowserFrameView::Layout() {
   OpaqueBrowserFrameView::Layout();
 
   if (!keyboard_)
     return;
 
   keyboard_->SetVisible(keyboard_showing_);
   keyboard_->SetBounds(GetBoundsForReservedArea());
 }
 
+void TouchBrowserFrameView::FocusWillChange(views::View* focused_before,
+                                            views::View* focused_now) {
+  if (!focused_before ||
+      (focused_now && focused_now->GetContentType()
+          != focused_before->GetContentType())) {
+    // TODO: support other types of keyboard.

[bryeung, 2011/02/01 19:03:53]

this should have a name attached to it

[varunjain, 2011/02/04 00:11:39]

Done.

+    UpdateKeyboardAndLayout(
+        focused_now->GetContentType() == views::View::GENERIC_INPUT);
+  }
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 // TouchBrowserFrameView, protected:
 int TouchBrowserFrameView::GetReservedHeight() const {
   if (keyboard_showing_)
     return kKeyboardHeight;
 
   return 0;
 }
 
+void TouchBrowserFrameView::ViewHierarchyChanged(bool is_add,
+                                                 View* parent,
+                                                 View* child) {
+  OpaqueBrowserFrameView::ViewHierarchyChanged(is_add, parent, child);
+  if (is_add && child == this && !focus_listener_added_ && GetFocusManager()) {

[bryeung, 2011/02/01 19:03:53]

Maybe this would be easier to understand if you pulled out the common
conditions?  Chromium style would encourage you to early exit if
(!GetFocusManager() || child != this).

[varunjain, 2011/02/04 00:11:39]

Done.

+    // Add focus listener when this view is added to the hierarchy.
+    GetFocusManager()->AddFocusChangeListener(this);
+    focus_listener_added_ = true;
+  } else if (!is_add && child == this
+      && focus_listener_added_ && GetFocusManager()) {
+    // Remove focus listener when this view is removed from the hierarchy.
+    GetFocusManager()->RemoveFocusChangeListener(this);
+    focus_listener_added_ = false;
+  }
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 // TouchBrowserFrameView, private:
 
 void TouchBrowserFrameView::InitVirtualKeyboard() {
   if (keyboard_)
     return;
 
   Profile* keyboard_profile = browser_view()->browser()->profile();
   DCHECK(keyboard_profile) << "Profile required for virtual keyboard.";
 
@@ skipping 60 matching lines @@
     Browser* source_browser = Browser::GetBrowserForController(
         Source<NavigationController>(source).ptr(), NULL);
     // If the Browser for the keyboard has navigated, hide the keyboard.
     if (source_browser == browser)
       UpdateKeyboardAndLayout(false);
   } else if (type == NotificationType::TAB_CONTENTS_DESTROYED) {
     GetFocusedStateAccessor()->DeleteProperty(
         Source<TabContents>(source).ptr()->property_bag());
   }
 }