Update browser accessibility tree on a renderer accessibility object state ch...

chrome/browser/browser_accessibility_manager_win.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/browser_accessibility_manager_win.h"
 
 #include "chrome/browser/browser_accessibility_win.h"
 #include "chrome/browser/renderer_host/render_process_host.h"
 #include "chrome/browser/renderer_host/render_view_host.h"
 #include "chrome/common/render_messages.h"
@@ skipping 96 matching lines @@
 
   LONG child_id = iter->second;
   base::hash_map<LONG, BrowserAccessibility*>::iterator uniq_iter =
     child_id_map_.find(child_id);
   if (uniq_iter != child_id_map_.end())
     focus_ = uniq_iter->second;
   ::NotifyWinEvent(EVENT_OBJECT_FOCUS, parent_hwnd_, OBJID_CLIENT, child_id);
 }
 
 void BrowserAccessibilityManager::OnAccessibilityObjectStateChange(
-    int renderer_id) {
-  base::hash_map<int, LONG>::iterator iter =
-      renderer_id_to_child_id_map_.find(renderer_id);
-  if (iter == renderer_id_to_child_id_map_.end())
-    return;
+    const webkit_glue::WebAccessibility& acc_obj) {
+  BrowserAccessibility* new_browser_acc = UpdateTree(acc_obj);
 
-  LONG child_id = iter->second;
-  ::NotifyWinEvent(
+  NotifyWinEvent(
       EVENT_OBJECT_STATECHANGE,
       parent_hwnd_,
       OBJID_CLIENT,
-      child_id);
+      new_browser_acc->child_id());
 }
 
 void BrowserAccessibilityManager::OnAccessibilityObjectChildrenChange(
     const std::vector<webkit_glue::WebAccessibility>& acc_changes) {
   if (delegate_)
     delegate_->AccessibilityObjectChildrenChangeAck();
 
   // For each accessibility object child change.
   for (unsigned int index = 0; index < acc_changes.size(); index++) {
     const webkit_glue::WebAccessibility& acc_obj = acc_changes[index];
-    base::hash_map<int, LONG>::iterator iter =
-        renderer_id_to_child_id_map_.find(acc_obj.id);
-    if (iter == renderer_id_to_child_id_map_.end())
-      continue;
+    BrowserAccessibility* new_browser_acc = UpdateTree(acc_obj);
 
-    LONG child_id = iter->second;
-    BrowserAccessibility* old_browser_acc = GetFromChildID(child_id);
+    LONG child_id;
+    if (root_ != new_browser_acc) {
+      child_id = new_browser_acc->GetParent()->child_id();
+    } else {
+      child_id = CHILDID_SELF;
+    }
+
+    NotifyWinEvent(EVENT_OBJECT_REORDER, parent_hwnd_, OBJID_CLIENT, child_id);
+  }
+}
+
+BrowserAccessibility* BrowserAccessibilityManager::UpdateTree(
+    const webkit_glue::WebAccessibility& acc_obj) {
+  base::hash_map<int, LONG>::iterator iter =
+      renderer_id_to_child_id_map_.find(acc_obj.id);
+  if (iter == renderer_id_to_child_id_map_.end())
+    return NULL;
+
+  LONG child_id = iter->second;
+  BrowserAccessibility* old_browser_acc = GetFromChildID(child_id);
+
+  if (old_browser_acc->GetChildCount() == 0 && acc_obj.children.size() == 0) {
+    // Reinitialize the BrowserAccessibility if there are no children to update.
+    old_browser_acc->Initialize(
+      this,

[dmazzoni, 2010/09/01 15:10:52]

nit: Indent 4 spaces

[Chris Guillory, 2010/09/01 15:35:27]

Done.

+      old_browser_acc->GetParent(),
+      child_id,
+      old_browser_acc->index_in_parent(),
+      acc_obj);
+
+    return old_browser_acc;
+  } else {
+    BrowserAccessibility* old_focus = focus_;
 
     BrowserAccessibility* new_browser_acc = CreateAccessibilityTree(
         old_browser_acc->GetParent(),
         child_id,
         acc_obj,
         old_browser_acc->index_in_parent());
 
-    if (focus_->IsDescendantOf(old_browser_acc))
+    if (focus_->IsDescendantOf(old_browser_acc)) {

[dmazzoni, 2010/09/01 15:10:52]

We definitely need to fix the focus (it can't point to an invalid node), but
should we be setting it to this parent node?

Maybe the state change notification from the renderer to the browser should pass
along the (new id) of the focused node?

[Chris Guillory, 2010/09/01 15:35:27]

That's a good thought. I remove this for now as this portion isn't tested
currently.

       focus_ = new_browser_acc;
 
+      if (delegate_)
+        delegate_->SetAccessibilityFocus(focus_->renderer_id());
+    }
+
     if (old_browser_acc->GetParent()) {
       old_browser_acc->GetParent()->ReplaceChild(
           old_browser_acc,
           new_browser_acc);
     } else {
       DCHECK_EQ(old_browser_acc, root_);
       root_ = new_browser_acc;
     }
     old_browser_acc->InactivateTree();
     old_browser_acc->Release();
     child_id_map_[child_id] = new_browser_acc;
 
-    if (root_ != new_browser_acc) {
+    if (focus_ != old_focus) {
       NotifyWinEvent(
-          EVENT_OBJECT_REORDER, parent_hwnd_, OBJID_CLIENT, child_id);
-    } else {
-      NotifyWinEvent(
-          EVENT_OBJECT_REORDER, parent_hwnd_, OBJID_CLIENT, CHILDID_SELF);
+          EVENT_OBJECT_FOCUS, parent_hwnd_, OBJID_CLIENT, focus_->child_id());
     }
+
+    return new_browser_acc;
   }
 }
 
 LONG 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.
   next_child_id_--;
   if (next_child_id_ == -2000000000)
@@ skipping 15 matching lines @@
   if ((src.state >> WebAccessibility::STATE_FOCUSED) & 1)
     focus_ = instance;
   for (int i = 0; i < static_cast<int>(src.children.size()); ++i) {
     BrowserAccessibility* child = CreateAccessibilityTree(
         instance, GetNextChildID(), src.children[i], i);
     instance->AddChild(child);
   }
 
   return instance;
 }