Fix to enable toggling accessibility using Ctrl+Alt+Z

chrome/browser/chromeos/login/wizard_accessibility_helper.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/chromeos/login/wizard_accessibility_helper.h"
 
 #include "base/logging.h"
 #include "base/stl_util-inl.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/extensions/extension_accessibility_api.h"
 #include "chrome/browser/prefs/pref_service.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/common/notification_registrar.h"
 #include "chrome/common/notification_service.h"
 #include "chrome/common/pref_names.h"
 #include "views/accelerator.h"
 #include "views/view.h"
 
 namespace chromeos {
 
 scoped_ptr<views::Accelerator> WizardAccessibilityHelper::accelerator_;
 
 // static
 views::Accelerator WizardAccessibilityHelper::GetAccelerator() {
   // Use an accelerator that would never match any hotkey to temporarily
   // disable the accessibility hotkey per http://crosbug.com/9195
   // TODO(xiyuan): Change back to real hotkey as the following
   //      new views::Accelerator(app::VKEY_Z, false, true, true)

[xiyuan, 2010/12/15 22:44:52]

please remove the TODO since you re-enabled the hotkey.

   if (!WizardAccessibilityHelper::accelerator_.get())
     WizardAccessibilityHelper::accelerator_.reset(
-        new views::Accelerator(app::VKEY_UNKNOWN, 0xdeadbeef));
+        new views::Accelerator(app::VKEY_Z, false, true, true));
   return *(WizardAccessibilityHelper::accelerator_.get());
 }
 
 // static
 WizardAccessibilityHelper* WizardAccessibilityHelper::GetInstance() {
   return Singleton<WizardAccessibilityHelper>::get();
 }
 
 WizardAccessibilityHelper::WizardAccessibilityHelper() {
   accessibility_handler_.reset(new WizardAccessibilityHandler());
@@ skipping 20 matching lines @@
   registered_notifications_ = true;
 }
 
 void WizardAccessibilityHelper::UnregisterNotifications() {
   if (!registered_notifications_)
     return;
   registrar_.RemoveAll();
   registered_notifications_ = false;
 }
 
+bool WizardAccessibilityHelper::IsAccessibilityEnabled() {
+  return g_browser_process &&
+      g_browser_process->local_state()->GetBoolean(
+      prefs::kAccessibilityEnabled);
+}
+
 void WizardAccessibilityHelper::MaybeEnableAccessibility(
     views::View* view_tree) {
-  if (g_browser_process &&
-      g_browser_process->local_state()->GetBoolean(
-          prefs::kAccessibilityEnabled)) {
-      EnableAccessibility(view_tree);
+  if (IsAccessibilityEnabled()) {
+    EnableAccessibilityForView(view_tree);
   } else {
     AddViewToBuffer(view_tree);
   }
 }
 
 void WizardAccessibilityHelper::MaybeSpeak(const char* str, bool queue,
     bool interruptible) {
-  if (g_browser_process &&
-      g_browser_process->local_state()->GetBoolean(
-          prefs::kAccessibilityEnabled)) {
+  if (IsAccessibilityEnabled()) {
     accessibility_handler_->Speak(str, queue, interruptible);
   }
 }
 
-void WizardAccessibilityHelper::EnableAccessibility(views::View* view_tree) {
+void WizardAccessibilityHelper::EnableAccessibilityForView(
+    views::View* view_tree) {
   VLOG(1) << "Enabling accessibility.";
   if (!registered_notifications_)
     RegisterNotifications();
-  if (g_browser_process) {
-    PrefService* prefService = g_browser_process->local_state();
-    if (!prefService->GetBoolean(prefs::kAccessibilityEnabled)) {
-      prefService->SetBoolean(prefs::kAccessibilityEnabled, true);
-      prefService->ScheduleSavePersistentPrefs();
-    }
-  }
-  ExtensionAccessibilityEventRouter::GetInstance()->
-      SetAccessibilityEnabled(true);
-  AddViewToBuffer(view_tree);
-  // If accessibility pref is set, enable accessibility for all views in
-  // the buffer for which access is not yet enabled.
-  for (std::map<views::View*, bool>::iterator iter =
-      views_buffer_.begin();
-      iter != views_buffer_.end(); ++iter) {
-    if (!(*iter).second) {
-      AccessibleViewHelper *helper = new AccessibleViewHelper((*iter).first,
-          profile_);
-      accessible_view_helpers_.push_back(helper);
-      (*iter).second = true;
+  SetAccessibilityEnabled(true);
+  if (view_tree) {
+    AddViewToBuffer(view_tree);
+    // If accessibility pref is set, enable accessibility for all views in
+    // the buffer for which access is not yet enabled.
+    for (std::map<views::View*, bool>::iterator iter =
+        views_buffer_.begin();
+        iter != views_buffer_.end(); ++iter) {
+      if (!(*iter).second) {
+        AccessibleViewHelper *helper = new AccessibleViewHelper((*iter).first,
+            profile_);
+        accessible_view_helpers_.push_back(helper);
+        (*iter).second = true;
+      }
     }
   }
 }
 
+void WizardAccessibilityHelper::ToggleAccessibility(views::View* view_tree) {
+  if (!IsAccessibilityEnabled()) {
+    EnableAccessibilityForView(view_tree);
+  } else {
+    SetAccessibilityEnabled(false);
+  }
+}
+
+void WizardAccessibilityHelper::SetAccessibilityEnabled(bool enabled) {
+  if (g_browser_process) {
+    PrefService* prefService = g_browser_process->local_state();
+    prefService->SetBoolean(prefs::kAccessibilityEnabled, enabled);
+    prefService->ScheduleSavePersistentPrefs();
+  }
+  ExtensionAccessibilityEventRouter::GetInstance()->
+      SetAccessibilityEnabled(enabled);
+  accessibility_handler_->Speak(enabled ? "Accessibility turned on." :
+      "Accessibility turned off",

[xiyuan, 2010/12/15 22:44:52]

Do we need to move the string literals into resources grd?

Out of curiosity, would i18n be supported?

+      false, true);
+}
+
 void WizardAccessibilityHelper::AddViewToBuffer(views::View* view_tree) {
   if (!view_tree->GetWidget())
     return;
   bool view_exists = false;
   // Check if the view is already queued for enabling accessibility.
   // Prevent adding the same view in the buffer twice.
   for (std::map<views::View*, bool>::iterator iter = views_buffer_.begin();
       iter != views_buffer_.end(); ++iter) {
     if ((*iter).first == view_tree) {
       view_exists = true;
       break;
     }
   }
   if (!view_exists)
     views_buffer_[view_tree] = false;
 }
 
 }  // namespace chromeos