Fix the white flicker of the keyboard overlay when it first appearing.

chrome/browser/ui/views/keyboard_overlay_delegate.cc

 // Copyright (c) 2012 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/views/keyboard_overlay_delegate.h"
 
 #include <algorithm>
 
 #include "base/utf_string_conversions.h"
-#include "chrome/browser/ui/views/web_dialog_view.h"
+#include "chrome/browser/ui/views/keyboard_overlay_dialog_view.h"
 #include "chrome/common/url_constants.h"
+#include "content/public/browser/notification_source.h"
+#include "content/public/browser/notification_types.h"
+#include "content/public/browser/render_view_host.h"
+#include "content/public/browser/render_widget_host.h"
+#include "content/public/browser/web_contents.h"
 #include "googleurl/src/gurl.h"
 #include "grit/generated_resources.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/gfx/screen.h"
 #include "ui/views/widget/widget.h"
 
 using content::WebContents;
 using content::WebUIMessageHandler;
 
 namespace {
 
 const int kBaseWidth = 1252;
 const int kBaseHeight = 516;
 const int kHorizontalMargin = 28;
 
 }  // namespace
 
 KeyboardOverlayDelegate::KeyboardOverlayDelegate(const string16& title)
     : title_(title),
-      view_(NULL) {
+      view_(NULL),
+      loaded_(false) {
 }
 
 KeyboardOverlayDelegate::~KeyboardOverlayDelegate() {
 }
 
+void KeyboardOverlayDelegate::Show(KeyboardOverlayDialogView* view) {
+  view_ = view;
+
+  views::Widget* widget = new views::Widget;
+  views::Widget::InitParams params(
+      views::Widget::InitParams::TYPE_WINDOW_FRAMELESS);
+  params.delegate = view;
+  widget->Init(params);
+
+  // Show the widget at the bottom of the work area.
+  gfx::Size size;
+  GetDialogSize(&size);
+  const gfx::Rect& rect = gfx::Screen::GetMonitorNearestWindow(
+      widget->GetNativeView()).work_area();
+  gfx::Rect bounds((rect.width() - size.width()) / 2,
+                   rect.height() - size.height(),
+                   size.width(),
+                   size.height());
+  widget->SetBounds(bounds);
+
+  widget->Show();
+
+  // Make the widget invisible until the web contents gets ready to display.
+  widget->SetOpacity(0);

[Ben Goodger (Google), 2012/05/30 20:49:12]

Can we just get away with not calling Show() here instead of messing with the
opacity?

[mazda, 2012/05/31 00:22:17]

I could remove SetOpacity by delaying calling Show().
I didn't know the web content is loaded without calling Show().
Thanks!

+}
+
 ui::ModalType KeyboardOverlayDelegate::GetDialogModalType() const {
   return ui::MODAL_TYPE_SYSTEM;
 }
 
 string16 KeyboardOverlayDelegate::GetDialogTitle() const {
   return title_;
 }
 
 GURL KeyboardOverlayDelegate::GetDialogContentURL() const {
   std::string url_string(chrome::kChromeUIKeyboardOverlayURL);
@@ skipping 12 matching lines @@
       view_->GetWidget()->GetNativeView()).bounds();
   const int width = min(kBaseWidth, rect.width() - kHorizontalMargin);
   const int height = width * kBaseHeight / kBaseWidth;
   size->SetSize(width, height);
 }
 
 std::string KeyboardOverlayDelegate::GetDialogArgs() const {
   return "[]";
 }
 
+void KeyboardOverlayDelegate::OnDialogShown(
+    content::WebUI* webui,
+    content::RenderViewHost* render_view_host) {
+  registrar_.Add(this,
+                 content::NOTIFICATION_LOAD_COMPLETED_MAIN_FRAME,
+                 content::Source<content::WebContents>(
+                     webui->GetWebContents()));
+  registrar_.Add(this,
+                 content::NOTIFICATION_RENDER_WIDGET_HOST_DID_PAINT,
+                 content::Source<content::RenderWidgetHost>(render_view_host));
+}
+
 void KeyboardOverlayDelegate::OnDialogClosed(
     const std::string& json_retval) {
   delete this;
   return;
 }
 
 void KeyboardOverlayDelegate::OnCloseContents(WebContents* source,
                                               bool* out_close_dialog) {
 }
 
 bool KeyboardOverlayDelegate::ShouldShowDialogTitle() const {
   return false;
 }
 
 bool KeyboardOverlayDelegate::HandleContextMenu(
     const content::ContextMenuParams& params) {
   return true;
 }
+
+void KeyboardOverlayDelegate::Observe(
+    int type,
+    const content::NotificationSource& source,
+    const content::NotificationDetails& details) {
+  switch (type) {
+    case content::NOTIFICATION_LOAD_COMPLETED_MAIN_FRAME:
+      registrar_.Remove(this,
+                        content::NOTIFICATION_LOAD_COMPLETED_MAIN_FRAME,
+                        source);
+      loaded_ = true;
+      break;
+    case content::NOTIFICATION_RENDER_WIDGET_HOST_DID_PAINT:
+      if (!loaded_)
+        break;
+      registrar_.Remove(this,
+                        content::NOTIFICATION_RENDER_WIDGET_HOST_DID_PAINT,
+                        source);
+      view_->GetWidget()->SetOpacity(255);
+      break;
+    default:
+      NOTREACHED() << "Unknown type: " << type;
+  }
+}