Add a big grab bag of missing web accessibility functionality...

content/browser/accessibility/browser_accessibility_manager.cc

 // Copyright (c) 2011 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 "content/browser/accessibility/browser_accessibility_manager.h"
 
 #include "base/logging.h"
 #include "content/browser/accessibility/browser_accessibility.h"
 #include "content/common/view_messages.h"
 
@@ skipping 43 matching lines @@
 
 BrowserAccessibilityManager::BrowserAccessibilityManager(
     gfx::NativeView parent_view,
     const WebAccessibility& src,
     BrowserAccessibilityDelegate* delegate,
     BrowserAccessibilityFactory* factory)
     : parent_view_(parent_view),
       delegate_(delegate),
       factory_(factory),
       focus_(NULL) {
-  root_ = CreateAccessibilityTree(NULL, src, 0);
+  root_ = CreateAccessibilityTree(NULL, src, 0, false);
   if (!focus_)
     SetFocus(root_, false);
 }
 
 // static
 int32 BrowserAccessibilityManager::GetNextChildID() {
   // Get the next child ID, and wrap around when we get near the end
   // of a 32-bit integer range. It's okay to wrap around; we just want
   // to avoid it as long as possible because clients may cache the ID of
   // an object for a while to determine if they've seen it before.
@@ skipping 25 matching lines @@
     return iter->second;
   } else {
     return NULL;
   }
 }
 
 BrowserAccessibility* BrowserAccessibilityManager::GetFromRendererID(
     int32 renderer_id) {
   base::hash_map<int32, int32>::iterator iter =
       renderer_id_to_child_id_map_.find(renderer_id);
-  if (iter == renderer_id_to_child_id_map_.end())
+  if (iter == renderer_id_to_child_id_map_.end()) {

[David Tseng, 2011/08/26 16:14:37]

nit: Do we need the braces?

[dmazzoni, 2011/08/29 18:08:51]

Done.

     return NULL;
+  }
 
   int32 child_id = iter->second;
   return GetFromChildID(child_id);
 }
 
 void BrowserAccessibilityManager::Remove(int32 child_id, int32 renderer_id) {
   child_id_map_.erase(child_id);
 
   // TODO(ctguil): Investigate if hit. We should never have a newer entry.
   DCHECK(renderer_id_to_child_id_map_[renderer_id] == child_id);
   // Make sure we don't overwrite a newer entry (see UpdateNode for a possible
   // corner case).
   if (renderer_id_to_child_id_map_[renderer_id] == child_id)
     renderer_id_to_child_id_map_.erase(renderer_id);
 }
 
 void BrowserAccessibilityManager::OnAccessibilityNotifications(
     const std::vector<ViewHostMsg_AccessibilityNotification_Params>& params) {
   for (uint32 index = 0; index < params.size(); index++) {
     const ViewHostMsg_AccessibilityNotification_Params& param = params[index];
 
     switch (param.notification_type) {
       case ViewHostMsg_AccessibilityNotification_Type::
-          NOTIFICATION_TYPE_CHECK_STATE_CHANGED:
-        OnAccessibilityObjectStateChange(param.acc_obj);
-        break;
+          NOTIFICATION_TYPE_LIVE_REGION_CHANGED:

[David Tseng, 2011/08/26 16:14:37]

nit: sort alphabetically.

[dmazzoni, 2011/08/29 18:08:51]

Done.

       case ViewHostMsg_AccessibilityNotification_Type::
           NOTIFICATION_TYPE_CHILDREN_CHANGED:
-        OnAccessibilityObjectChildrenChange(param.acc_obj);
+        // Notifications where children are included.
+        OnSimpleAccessibilityNotification(
+            param.acc_obj, param.notification_type, true);
         break;
       case ViewHostMsg_AccessibilityNotification_Type::
           NOTIFICATION_TYPE_FOCUS_CHANGED:
         OnAccessibilityObjectFocusChange(param.acc_obj);
         break;
       case ViewHostMsg_AccessibilityNotification_Type::
           NOTIFICATION_TYPE_LOAD_COMPLETE:
         OnAccessibilityObjectLoadComplete(param.acc_obj);
         break;
-      case ViewHostMsg_AccessibilityNotification_Type::
-          NOTIFICATION_TYPE_VALUE_CHANGED:
-        OnAccessibilityObjectValueChange(param.acc_obj);
-        break;
-      case ViewHostMsg_AccessibilityNotification_Type::
-          NOTIFICATION_TYPE_SELECTED_TEXT_CHANGED:
-        OnAccessibilityObjectTextChange(param.acc_obj);
-        break;
       default:
-        DCHECK(0);
+        // For all other notifications, children are not included.

[David Tseng, 2011/08/26 16:14:37]

Either remove the DCHECK above or explicitly list the other notifications that
exclude descendants (without which I think clang will generate a warning).

[dmazzoni, 2011/08/29 18:08:51]

Done.

+        OnSimpleAccessibilityNotification(
+            param.acc_obj, param.notification_type, false);
         break;
     }
   }
 }
 
-void BrowserAccessibilityManager::OnAccessibilityObjectStateChange(
-    const WebAccessibility& acc_obj) {
-  BrowserAccessibility* new_browser_acc = UpdateNode(acc_obj, false);
+void BrowserAccessibilityManager::OnSimpleAccessibilityNotification(
+    const WebAccessibility& acc_obj,
+    int notification_type,
+    bool include_children) {
+  BrowserAccessibility* new_browser_acc =
+      UpdateNode(acc_obj, include_children);
   if (!new_browser_acc)
     return;
 
-  NotifyAccessibilityEvent(
-      ViewHostMsg_AccessibilityNotification_Type::
-          NOTIFICATION_TYPE_CHECK_STATE_CHANGED,
-      new_browser_acc);
-}
-
-void BrowserAccessibilityManager::OnAccessibilityObjectChildrenChange(
-    const WebAccessibility& acc_obj) {
-  BrowserAccessibility* new_browser_acc = UpdateNode(acc_obj, true);
-  if (!new_browser_acc)
-    return;
-
-  NotifyAccessibilityEvent(
-      ViewHostMsg_AccessibilityNotification_Type::
-          NOTIFICATION_TYPE_CHILDREN_CHANGED,
-      new_browser_acc);
+  NotifyAccessibilityEvent(notification_type, new_browser_acc);
 }
 
 void BrowserAccessibilityManager::OnAccessibilityObjectFocusChange(
   const WebAccessibility& acc_obj) {
   BrowserAccessibility* new_browser_acc = UpdateNode(acc_obj, false);
   if (!new_browser_acc)
     return;
 
   SetFocus(new_browser_acc, false);
   if (delegate_ && delegate_->HasFocus()) {
@@ skipping 16 matching lines @@
     SetFocus(root_, false);
 
   NotifyAccessibilityEvent(
       ViewHostMsg_AccessibilityNotification_Type::
           NOTIFICATION_TYPE_LOAD_COMPLETE,
       root_);
   if (delegate_ && delegate_->HasFocus())
     GotFocus();
 }
 
-void BrowserAccessibilityManager::OnAccessibilityObjectValueChange(
-    const WebAccessibility& acc_obj) {
-  BrowserAccessibility* new_browser_acc = UpdateNode(acc_obj, false);
-  if (!new_browser_acc)
-    return;
-
-  NotifyAccessibilityEvent(
-      ViewHostMsg_AccessibilityNotification_Type::
-          NOTIFICATION_TYPE_VALUE_CHANGED,
-      new_browser_acc);
-}
-
-void BrowserAccessibilityManager::OnAccessibilityObjectTextChange(
-    const WebAccessibility& acc_obj) {
-  BrowserAccessibility* new_browser_acc = UpdateNode(acc_obj, false);
-  if (!new_browser_acc)
-    return;
-
-  NotifyAccessibilityEvent(
-      ViewHostMsg_AccessibilityNotification_Type::
-          NOTIFICATION_TYPE_SELECTED_TEXT_CHANGED,
-      new_browser_acc);
-}
-
 void BrowserAccessibilityManager::GotFocus() {
   // TODO(ctguil): Remove when tree update logic handles focus changes.
   if (!focus_)
     return;
 
   NotifyAccessibilityEvent(
       ViewHostMsg_AccessibilityNotification_Type::
           NOTIFICATION_TYPE_FOCUS_CHANGED,
       focus_);
 }
@@ skipping 50 matching lines @@
     return NULL;
 
   if (!include_children) {
     DCHECK_EQ(0U, src.children.size());
     current->Initialize(
         this,
         current->parent(),
         current->child_id(),
         current->index_in_parent(),
         src);
+    current->SendNodeUpdateEvents();
     return current;
   }
 
   BrowserAccessibility* current_parent = current->parent();
   int current_index_in_parent = current->index_in_parent();
 
   // Detach all of the nodes in the old tree and get a single flat vector
   // of all node pointers.
   std::vector<BrowserAccessibility*> old_tree_nodes;
   current->DetachTree(&old_tree_nodes);
 
   // Build a new tree, reusing old nodes if possible. Each node that's
   // reused will have its reference count incremented by one.
-  current =
-      CreateAccessibilityTree(current_parent, src, current_index_in_parent);
+  current = CreateAccessibilityTree(
+      current_parent, src, current_index_in_parent, true);
 
   // Decrement the reference count of all nodes in the old tree, which will
   // delete any nodes no longer needed.
-  for (int i = 0; i < static_cast<int>(old_tree_nodes.size()); i++)
+  for (int i = 0; i < static_cast<int>(old_tree_nodes.size()); i++) {

[David Tseng, 2011/08/26 16:14:37]

nit: braces necessary?

[dmazzoni, 2011/08/29 18:08:51]

Done.

     old_tree_nodes[i]->InternalReleaseReference(false);
+  }
 
   if (!focus_ || !focus_->instance_active())
     SetFocus(root_, false);
 
   return current;
 }
 
 BrowserAccessibility* BrowserAccessibilityManager::CreateAccessibilityTree(
     BrowserAccessibility* parent,
     const WebAccessibility& src,
-    int index_in_parent) {
+    int index_in_parent,
+    bool send_show_events) {
   BrowserAccessibility* instance = NULL;
   int32 child_id = 0;
+  bool children_can_send_show_events = send_show_events;
   base::hash_map<int32, int32>::iterator iter =
       renderer_id_to_child_id_map_.find(src.id);
 
   // If a BrowserAccessibility instance for this ID already exists, add a
   // new reference to it and retrieve its children vector.
   if (iter != renderer_id_to_child_id_map_.end()) {
     child_id = iter->second;
     instance = GetFromChildID(child_id);
   }
 
   // If the node has changed roles, don't reuse a BrowserAccessibility
   // object, that could confuse a screen reader.
   // TODO(dtseng): Investigate when this gets hit; See crbug.com/93095.
   DCHECK(!instance || instance->role() == src.role);
 
   // If we're reusing a node, it should already be detached from a parent
   // and any children. If not, that means we have a serious bug somewhere,
   // like the same child is reachable from two places in the same tree.
   if (instance && (instance->parent() != NULL || instance->child_count() > 0)) {
     NOTREACHED();
     instance = NULL;
   }
 
   if (instance) {
     // If we're reusing a node, update its parent and increment its
     // reference count.
     instance->UpdateParent(parent, index_in_parent);
     instance->InternalAddReference();
+    send_show_events = false;
   } else {
     // Otherwise, create a new instance.
     instance = factory_->Create();
     child_id = GetNextChildID();
+    children_can_send_show_events = false;
   }
 
   instance->Initialize(this, parent, child_id, index_in_parent, src);
   child_id_map_[child_id] = instance;
   renderer_id_to_child_id_map_[src.id] = child_id;
   if ((src.state >> WebAccessibility::STATE_FOCUSED) & 1)
     SetFocus(instance, false);
   for (int i = 0; i < static_cast<int>(src.children.size()); ++i) {
     BrowserAccessibility* child = CreateAccessibilityTree(
-        instance, src.children[i], i);
+        instance, src.children[i], i, children_can_send_show_events);
     instance->AddChild(child);
   }
+  if (send_show_events) {

[David Tseng, 2011/08/26 16:14:37]

Any chance we could move this up to UpdateNode?

[dmazzoni, 2011/08/29 18:08:51]

It'd be pretty hard, we need to update children_can_send_show_events as part of
the recursive call.

I added a comment to try to explain it better.

Essentially what we need to do is send a SHOW event for the root of a subtree
that just appeared for the first time, but not for any of its descendants.

+    NotifyAccessibilityEvent(
+        ViewHostMsg_AccessibilityNotification_Type::
+            NOTIFICATION_TYPE_OBJECT_SHOW,
+            instance);

[David Tseng, 2011/08/26 16:14:37]

nit: align with "ViewHostMsg_AccessibilityNotification_Type::
"

[dmazzoni, 2011/08/29 18:08:51]

Done.

+  }
+  instance->SendNodeUpdateEvents();
 
   return instance;
 }