Support additional webkit accessibility notifications and states.

chrome/renderer/render_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/renderer/render_view.h"
 
 #include <algorithm>
 #include <string>
 #include <vector>
 
@@ skipping 647 matching lines @@
   if (opener_id == MSG_ROUTING_NONE) {
     did_show_ = true;
     CompleteInit(parent_hwnd);
   }
 
   host_window_ = parent_hwnd;
 
   const CommandLine& command_line = *CommandLine::ForCurrentProcess();
   if (command_line.HasSwitch(switches::kDomAutomationController))
     enabled_bindings_ |= BindingsPolicy::DOM_AUTOMATION;
+  if (command_line.HasSwitch(switches::kEnableAccessibility))
+    WebAccessibilityCache::enableAccessibility();
 
   audio_message_filter_ = new AudioMessageFilter(routing_id_);
   render_thread_->AddFilter(audio_message_filter_);
 }
 
 void RenderView::OnMessageReceived(const IPC::Message& message) {
   WebFrame* main_frame = webview() ? webview()->mainFrame() : NULL;
   if (main_frame)
     child_process_logging::SetActiveURL(main_frame->url());
 
@@ skipping 119 matching lines @@
     IPC_MESSAGE_HANDLER(ViewMsg_WindowFrameChanged, OnWindowFrameChanged)
 #endif
     IPC_MESSAGE_HANDLER(ViewMsg_SetEditCommandsForNextKeyEvent,
                         OnSetEditCommandsForNextKeyEvent)
     IPC_MESSAGE_HANDLER(ViewMsg_ExecuteCode,
                         OnExecuteCode)
     IPC_MESSAGE_HANDLER(ViewMsg_CustomContextMenuAction,
                         OnCustomContextMenuAction)
     IPC_MESSAGE_HANDLER(ViewMsg_TranslatePage, OnTranslatePage)
     IPC_MESSAGE_HANDLER(ViewMsg_RevertTranslation, OnRevertTranslation)
-    IPC_MESSAGE_HANDLER(ViewMsg_GetAccessibilityTree, OnGetAccessibilityTree)
+    IPC_MESSAGE_HANDLER(ViewMsg_EnableAccessibility, OnEnableAccessibility)
     IPC_MESSAGE_HANDLER(ViewMsg_SetAccessibilityFocus, OnSetAccessibilityFocus)
     IPC_MESSAGE_HANDLER(ViewMsg_AccessibilityDoDefaultAction,
                         OnAccessibilityDoDefaultAction)
     IPC_MESSAGE_HANDLER(ViewMsg_AccessibilityNotifications_ACK,
                         OnAccessibilityNotificationsAck)
     IPC_MESSAGE_HANDLER(ViewMsg_OpenFileSystemRequest_Complete,
                         OnOpenFileSystemRequestComplete)
     IPC_MESSAGE_HANDLER(ViewMsg_AsyncOpenFile_ACK, OnAsyncFileOpened)
 
     // Have the super handle all other messages.
@@ skipping 653 matching lines @@
 
   // If we end up reusing this WebRequest (for example, due to a #ref click),
   // we don't want the transition type to persist.  Just clear it.
   navigation_state->set_transition_type(PageTransition::LINK);
 
   // Check if the navigation was within the same page, in which case we don't
   // want to clear the accessibility cache.
   if (accessibility_.get() && !navigation_state->was_within_same_page()) {
     accessibility_->clear();
     accessibility_.reset();
+    pending_accessibility_notifications_.clear();
   }
-  pending_accessibility_notifications_.clear();
 }
 
 // Tell the embedding application that the title of the active page has changed
 void RenderView::UpdateTitle(WebFrame* frame, const string16& title) {
   // Ignore all but top level navigations...
   if (!frame->parent()) {
     Send(new ViewHostMsg_UpdateTitle(
         routing_id_,
         page_id_,
         UTF16ToWideHack(title.length() > chrome::kMaxTitleChars ?
@@ skipping 2898 matching lines @@
 }
 
 void RenderView::OnNotifyRendererViewType(ViewType::Type type) {
   view_type_ = type;
 }
 
 void RenderView::OnUpdateBrowserWindowId(int window_id) {
   browser_window_id_ = window_id;
 }
 
-void RenderView::OnGetAccessibilityTree() {
-  if (accessibility_.get())
-    accessibility_->clear();
-    accessibility_.reset(WebAccessibilityCache::create());
-    accessibility_->initialize(webview());
-  pending_accessibility_notifications_.clear();
+void RenderView::OnEnableAccessibility() {
+  if (WebAccessibilityCache::accessibilityEnabled())
+    return;
 
-  WebAccessibilityObject src_tree = webview()->accessibilityObject();
-  WebAccessibility dst_tree(src_tree, accessibility_.get());
-  Send(new ViewHostMsg_AccessibilityTree(routing_id_, dst_tree));
+  WebAccessibilityCache::enableAccessibility();
+
+  if (webview()) {
+    // It's possible that the webview has already loaded a webpage without
+    // accessibility being enabled. Initialize the browser's cached
+    // accessibility tree by sending it a 'load complete' notification.
+    postAccessibilityNotification(
+        webview()->accessibilityObject(),
+        WebKit::WebAccessibilityNotificationLoadComplete);
+  }
 }
 
 void RenderView::OnSetAccessibilityFocus(int acc_obj_id) {
   if (!accessibility_.get())
     return;
   if (accessibility_->isValidId(acc_obj_id)) {
     // TODO(dmazzoni) fix the cache so that id=1000 is not a magic number.
     // By convention, calling SetFocus on the root of the tree (id = 1000)
     // should clear the current focus. Otherwise set the focus to the new
     // node.
@@ skipping 1039 matching lines @@
   GURL url(ds->request().url());
   Time start = state->start_load_time();
   Time finish = state->finish_load_time();
   // TODO(mbelshe): should we log more stats?
   LOG(INFO) << "PLT: "
             << (finish - start).InMilliseconds()
             << "ms "
             << url.spec();
 }
 
-void RenderView::focusAccessibilityObject(
-    const WebAccessibilityObject& acc_obj) {
-#if defined(OS_WIN)
-  // TODO(dglazkov): Current logic implies that focus change can only be made
-  // after at least one call to RenderView::OnGetAccessibilityInfo, which is
-  // where accessibility is initialized. We should determine whether that's
-  // right.
-  if (!accessibility_.get())
-    return;
-
-  // Retrieve the accessibility object id of the AccessibilityObject.
-  int acc_obj_id = accessibility_->addOrGetId(acc_obj);
-
-  // If id is valid, alert the browser side that an accessibility focus change
-  // occurred.
-  if (acc_obj_id >= 0)
-    Send(new ViewHostMsg_AccessibilityFocusChange(routing_id_, acc_obj_id));
-
-#else  // defined(OS_WIN)
-  // TODO(port): accessibility not yet implemented
-  NOTIMPLEMENTED();
-#endif
-}
-
 void RenderView::postAccessibilityNotification(
     const WebAccessibilityObject& obj,
     WebAccessibilityNotification notification) {
-  if (!accessibility_.get() || (accessibility_->addOrGetId(obj) < 0))
+  if (!accessibility_.get() && webview()) {
+    // Load complete should be our first notification sent.
+    // TODO(ctguil): Investigate if a different notification is a WebCore bug.
+    if (notification != WebKit::WebAccessibilityNotificationLoadComplete)
+      return;
+
+    // Create and initialize our accessibility cache
+    accessibility_.reset(WebAccessibilityCache::create());
+    accessibility_->initialize(webview());
+  }
+
+  // Add the accessibility object to our cache and ensure it's valid.
+  if (accessibility_->addOrGetId(obj) < 0)
     return;
 
   ViewHostMsg_AccessibilityNotification_Params param;
   switch (notification) {
     case WebKit::WebAccessibilityNotificationCheckedStateChanged:
       param.notification_type =
           ViewHostMsg_AccessibilityNotification_Params::
               NOTIFICATION_TYPE_CHECK_STATE_CHANGED;
       break;
     case WebKit::WebAccessibilityNotificationChildrenChanged:
       param.notification_type =
           ViewHostMsg_AccessibilityNotification_Params::
               NOTIFICATION_TYPE_CHILDREN_CHANGED;
       break;
+    case WebKit::WebAccessibilityNotificationFocusedUIElementChanged:
+      param.notification_type =
+          ViewHostMsg_AccessibilityNotification_Params::
+              NOTIFICATION_TYPE_FOCUS_CHANGED;
+      break;
+    case WebKit::WebAccessibilityNotificationLoadComplete:
+      param.notification_type =
+          ViewHostMsg_AccessibilityNotification_Params::
+              NOTIFICATION_TYPE_LOAD_COMPLETE;
+      break;
     case WebKit::WebAccessibilityNotificationValueChanged:
       param.notification_type =
           ViewHostMsg_AccessibilityNotification_Params::
               NOTIFICATION_TYPE_VALUE_CHANGED;
       break;
     default:
       return;
   }
   param.acc_obj = WebAccessibility(obj, accessibility_.get());
 
@@ skipping 315 matching lines @@
 }
 
 void RenderView::OnAsyncFileOpened(base::PlatformFileError error_code,
                                    IPC::PlatformFileForTransit file_for_transit,
                                    int message_id) {
   pepper_delegate_.OnAsyncFileOpened(
       error_code,
       IPC::PlatformFileForTransitToPlatformFile(file_for_transit),
       message_id);
 }