Rename confusing child_id to unique_id_win

content/browser/accessibility/browser_accessibility_win.cc

 // Copyright (c) 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 "content/browser/accessibility/browser_accessibility_win.h"
 
 #include <UIAutomationClient.h>
 #include <UIAutomationCoreApi.h>
 
 #include "base/string_number_conversions.h"
@@ skipping 14 matching lines @@
 // http://developer.mozilla.org/en/Accessibility/AT-APIs/ImplementationFeatures/MSAA
 const GUID GUID_ISimpleDOM = {
     0x0c539790, 0x12e4, 0x11cf,
     0xb6, 0x61, 0x00, 0xaa, 0x00, 0x4c, 0xd6, 0xd8};
 const GUID GUID_IAccessibleContentDocument = {
     0xa5d8e1f3, 0x3571, 0x4d8f,
     0x95, 0x21, 0x07, 0xed, 0x28, 0xfb, 0x07, 0x2e};
 
 const char16 BrowserAccessibilityWin::kEmbeddedCharacter[] = L"\xfffc";
 
+// static
+LONG BrowserAccessibilityWin::next_unique_id_win_ = -1;
+
 //
 // BrowserAccessibilityRelation
 //
 // A simple implementation of IAccessibleRelation, used to represent
 // a relationship between two accessible nodes in the tree.
 //
 
 class BrowserAccessibilityRelation
     : public CComObjectRootEx<CComMultiThreadModel>,
       public IAccessibleRelation {
@@ skipping 136 matching lines @@
   return static_cast<BrowserAccessibilityWin*>(this);
 }
 
 BrowserAccessibilityWin::BrowserAccessibilityWin()
     : ia_role_(0),
       ia_state_(0),
       ia2_role_(0),
       ia2_state_(0),
       first_time_(true),
       old_ia_state_(0) {
+  // Start unique IDs at -1 and decrement each time, because get_accChild
+  // uses positive IDs to enumerate children, so we use negative IDs to
+  // clearly distinguish between indices and unique IDs.
+  unique_id_win_ = next_unique_id_win_;
+  next_unique_id_win_--;
+  if (next_unique_id_win_ > 0)
+    next_unique_id_win_ = -1;
 }
 
 BrowserAccessibilityWin::~BrowserAccessibilityWin() {
   for (size_t i = 0; i < relations_.size(); ++i)
     relations_[i]->Release();
 }
 
 //
 // IAccessible methods.
 //
@@ skipping 460 matching lines @@
   return S_OK;
 }
 
 STDMETHODIMP BrowserAccessibilityWin::get_uniqueID(LONG* unique_id) {
   if (!instance_active_)
     return E_FAIL;
 
   if (!unique_id)
     return E_INVALIDARG;
 
-  *unique_id = child_id_;
+  *unique_id = unique_id_win_;
   return S_OK;
 }
 
 STDMETHODIMP BrowserAccessibilityWin::get_windowHandle(HWND* window_handle) {
   if (!instance_active_)
     return E_FAIL;
 
   if (!window_handle)
     return E_INVALIDARG;
 
@@ skipping 1561 matching lines @@
 
   string16 tag;
   if (GetStringAttribute(AccessibilityNodeData::ATTR_HTML_TAG, &tag))
     *node_name = SysAllocString(tag.c_str());
   else
     *node_name = NULL;
 
   *name_space_id = 0;
   *node_value = SysAllocString(value_.c_str());
   *num_children = children_.size();
-  *unique_id = child_id_;
+  *unique_id = unique_id_win_;
 
   if (ia_role_ == ROLE_SYSTEM_DOCUMENT) {
     *node_type = NODETYPE_DOCUMENT;
   } else if (ia_role_ == ROLE_SYSTEM_TEXT &&
              ((ia2_state_ & IA2_STATE_EDITABLE) == 0)) {
     *node_type = NODETYPE_TEXT;
   } else {
     *node_type = NODETYPE_ELEMENT;
   }
 
@@ skipping 608 matching lines @@
     // Normally focus events are handled elsewhere, however
     // focus for managed descendants is platform-specific.
     // Fire a focus event if the focused descendant in a multi-select
     // list box changes.
     if (role_ == AccessibilityNodeData::ROLE_LISTBOX_OPTION &&
         (ia_state_ & STATE_SYSTEM_FOCUSABLE) &&
         (ia_state_ & STATE_SYSTEM_SELECTABLE) &&
         (ia_state_ & STATE_SYSTEM_FOCUSED) &&
         !(old_ia_state_ & STATE_SYSTEM_FOCUSED)) {
       ::NotifyWinEvent(EVENT_OBJECT_FOCUS, hwnd,
-                       OBJID_CLIENT, child_id());
+                       OBJID_CLIENT, unique_id_win());
     }
 
     if ((ia_state_ & STATE_SYSTEM_SELECTED) &&
         !(old_ia_state_ & STATE_SYSTEM_SELECTED)) {
       ::NotifyWinEvent(EVENT_OBJECT_SELECTIONADD, hwnd,
-                       OBJID_CLIENT, child_id());
+                       OBJID_CLIENT, unique_id_win());
     } else if (!(ia_state_ & STATE_SYSTEM_SELECTED) &&
                (old_ia_state_ & STATE_SYSTEM_SELECTED)) {
       ::NotifyWinEvent(EVENT_OBJECT_SELECTIONREMOVE, hwnd,
-                       OBJID_CLIENT, child_id());
+                       OBJID_CLIENT, unique_id_win());
     }
 
     old_ia_state_ = ia_state_;
   }
 
   first_time_ = false;
 }
 
 void BrowserAccessibilityWin::NativeAddReference() {
   AddRef();
@@ skipping 17 matching lines @@
   if (var_id.vt != VT_I4)
     return NULL;
 
   LONG child_id = var_id.lVal;
   if (child_id == CHILDID_SELF)
     return this;
 
   if (child_id >= 1 && child_id <= static_cast<LONG>(children_.size()))
     return children_[child_id - 1]->ToBrowserAccessibilityWin();
 
-  return manager_->GetFromChildID(child_id)->ToBrowserAccessibilityWin();
+  return manager_->ToBrowserAccessibilityManagerWin()->
+      GetFromUniqueIdWin(child_id)->ToBrowserAccessibilityWin();

[aboxhall, 2013/04/09 09:28:29]

I don't think ToBrowserAccessibilityWin() is necessary here, is it?

[dmazzoni, 2013/04/09 19:44:04]

You're right, thanks.

 }
 
 HRESULT BrowserAccessibilityWin::GetStringAttributeAsBstr(
     AccessibilityNodeData::StringAttribute attribute,
     BSTR* value_bstr) {
   string16 str;
 
   if (!GetStringAttribute(attribute, &str))
     return S_FALSE;
 
@@ skipping 576 matching lines @@
   // The role should always be set.
   DCHECK(!role_name_.empty() || ia_role_);
 
   // If we didn't explicitly set the IAccessible2 role, make it the same
   // as the MSAA role.
   if (!ia2_role_)
     ia2_role_ = ia_role_;
 }
 
 }  // namespace content