Instant Extended: Fallback to local preview if the remote instant page is not ready on user input.

chrome/browser/instant/instant_controller.cc

 // Copyright 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/instant/instant_controller.h"
 
 #include "base/command_line.h"
 #include "base/metrics/histogram.h"
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
@@ skipping 353 matching lines @@
   // this, but it's not called in non-extended mode, so fake it.
   if (!extended_enabled_)
     search_mode_.mode = chrome::search::Mode::MODE_SEARCH_SUGGESTIONS;
 
   if (instant_tab_) {
     instant_tab_->Update(user_text, selection_start, selection_end, verbatim);
   } else {
     if (first_interaction_time_.is_null())
       first_interaction_time_ = base::Time::Now();
     allow_preview_to_show_search_suggestions_ = true;
+
+    // For extended mode, if the loader is not ready at this point, switch over
+    // to a backup loader.
+    if (extended_enabled_ && !loader_->supports_instant() &&
+        !loader_->IsUsingLocalPreview() && browser_->GetActiveWebContents()) {
+      CreateLoader(kLocalOmniboxPopupURL, browser_->GetActiveWebContents());
+      loader_->set_is_in_fallback_mode(true);
+    }
+
     loader_->Update(extended_enabled_ ? user_text : full_text,
                     selection_start, selection_end, verbatim);
   }
 
   content::NotificationService::current()->Notify(
       chrome::NOTIFICATION_INSTANT_CONTROLLER_UPDATED,
       content::Source<InstantController>(this),
       content::NotificationService::NoDetails());
 
   // We don't have new suggestions yet, but we can either reuse the existing
@@ skipping 530 matching lines @@
 
 void InstantController::OmniboxLostFocus(gfx::NativeView view_gaining_focus) {
   // If the preview is showing custom NTP content, don't hide it, commit it
   // (no matter where the user clicked) or try to recreate it.
   if (model_.mode().is_ntp())
     return;
 
   // If the preview is not showing at all, recreate it if it's stale.
   if (model_.mode().is_default()) {
     OnStaleLoader();
+    MaybeSwitchToRemoteLoader();
     return;
   }
 
   // The preview is showing search suggestions. If GetPreviewContents() is NULL,
   // we are in the commit path. Don't do anything.
   if (!GetPreviewContents())
     return;
 
 #if defined(OS_MACOSX)
   // TODO(sreeram): See if Mac really needs this special treatment.
@@ skipping 20 matching lines @@
 bool InstantController::EnsureLoaderIsCurrent() {
   // If we are on a search results page, we'll use that instead of a loader.
   if (instant_tab_)
     return true;
 
   // If there's no active tab, the browser is closing.
   content::WebContents* active_tab = browser_->GetActiveWebContents();
   if (!active_tab)
     return false;
 
+  // In fallback mode, we do not change the loader.
+  if (loader_ && loader_->is_in_fallback_mode())
+    return true;
+
   std::string instant_url;
   if (!GetInstantURL(active_tab, &instant_url)) {
     // If we are in extended mode, fallback to the local popup.
     if (extended_enabled_)
       instant_url = kLocalOmniboxPopupURL;
   }
 
   if (!loader_ || loader_->instant_url() != instant_url)
     CreateLoader(instant_url, active_tab);
 
   return true;
 }
 
 void InstantController::CreateLoader(const std::string& instant_url,
                                      content::WebContents* active_tab) {
   HideInternal();
   loader_.reset(new InstantLoader(this, instant_url));
   loader_->InitContents(active_tab);
 
   // Ensure the searchbox API has the correct initial state.
   if (extended_enabled_) {
     browser_->UpdateThemeInfoForPreview();
     loader_->SetDisplayInstantResults(instant_enabled_);
     loader_->SearchModeChanged(search_mode_);
     loader_->KeyCaptureChanged(omnibox_focus_state_ == OMNIBOX_FOCUS_INVISIBLE);
     loader_->SetMarginSize(start_margin_, end_margin_);
+    loader_->InitializeFonts();
   }
 
   // Restart the stale loader timer.
   stale_loader_timer_.Start(FROM_HERE,
       base::TimeDelta::FromMilliseconds(kStaleLoaderTimeoutMS), this,
       &InstantController::OnStaleLoader);
 }
 
 void InstantController::OnStaleLoader() {
   // The local popup is never stale.
   if (loader_ && loader_->IsUsingLocalPreview())
     return;
 
   // If the preview is showing or the omnibox has focus, don't delete the
   // loader. It will get refreshed the next time the preview is hidden or the
   // omnibox loses focus.
   if (!stale_loader_timer_.IsRunning() &&
       omnibox_focus_state_ == OMNIBOX_FOCUS_NONE &&
       model_.mode().is_default()) {
     loader_.reset();
     EnsureLoaderIsCurrent();
   }
 }
 
+void InstantController::MaybeSwitchToRemoteLoader() {
+  if (!loader_ || !loader_->is_in_fallback_mode() ||
+      omnibox_focus_state_ != OMNIBOX_FOCUS_NONE ||
+      !model_.mode().is_default()) {
+    return;
+  }
+
+  loader_->set_is_in_fallback_mode(false);
+  EnsureLoaderIsCurrent();
+}
+
 void InstantController::ResetInstantTab() {
   // Do not wire up the InstantTab if instant should only use local previews, to
   // prevent it from sending data to the page.
   if (search_mode_.is_origin_search() && !use_local_preview_only_) {
     content::WebContents* active_tab = browser_->GetActiveWebContents();
     if (!instant_tab_ || active_tab != instant_tab_->contents()) {
       instant_tab_.reset(new InstantTab(this, active_tab));
       instant_tab_->Init();
       instant_tab_->SetDisplayInstantResults(instant_enabled_);
       instant_tab_->SetMarginSize(start_margin_, end_margin_);
+      instant_tab_->InitializeFonts();
     }
 
     // Hide the |loader_| since we are now using |instant_tab_| instead.
     HideLoader();
   } else {
     instant_tab_.reset();
   }
 }
 
 void InstantController::HideLoader() {
   HideInternal();
   OnStaleLoader();
+  MaybeSwitchToRemoteLoader();
 }
 
 void InstantController::HideInternal() {
   DVLOG(1) << "Hide";
 
   // If GetPreviewContents() returns NULL, either we're already in the desired
   // MODE_DEFAULT state, or we're in the commit path. For the latter, don't
   // change the state just yet; else we may hide the preview unnecessarily.
   // Instead, the state will be set correctly after the commit is done.
   if (GetPreviewContents()) {
@@ skipping 146 matching lines @@
   std::map<std::string, int>::const_iterator iter =
       blacklisted_urls_.find(*instant_url);
   if (iter != blacklisted_urls_.end() &&
       iter->second > kMaxInstantSupportFailures) {
     RecordEventHistogram(INSTANT_CONTROLLER_EVENT_URL_BLOCKED_BY_BLACKLIST);
     return false;
   }
 
   return true;
 }