Add support for UIA accessibility interfaces like IAccessibleEx and IRawElementProviderSimple.

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 <atlsafe.h>

[dmazzoni, 2012/04/04 06:02:00]

Are you actually using atlsafe? I don't see CComSafeArray, etc.

[ananta, 2012/04/04 19:23:00]

Removed

+#include <UIAutomationClient.h>
+#include <UIAutomationCoreApi.h>
+
 #include "base/string_number_conversions.h"
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
 #include "base/win/enum_variant.h"
 #include "base/win/scoped_comptr.h"
+#include "base/win/windows_version.h"
 #include "content/browser/accessibility/browser_accessibility_manager_win.h"
 #include "content/common/accessibility_messages.h"
 #include "net/base/escape.h"
 #include "ui/base/accessibility/accessible_text_utils.h"
 
 using webkit_glue::WebAccessibility;
 
 // The GUID for the ISimpleDOM service is not defined in the IDL files.
 // This is taken directly from the Mozilla sources
 // (accessible/src/msaa/nsAccessNodeWrap.cpp) and it's also documented at:
@@ skipping 2483 matching lines @@
 
 //
 // IServiceProvider methods.
 //
 
 STDMETHODIMP BrowserAccessibilityWin::QueryService(
     REFGUID guidService, REFIID riid, void** object) {
   if (!instance_active_)
     return E_FAIL;
 
-  if (guidService == IID_IAccessible ||
-      guidService == IID_IAccessible2 ||
-      guidService == IID_IAccessibleAction ||
-      guidService == IID_IAccessibleHyperlink ||
-      guidService == IID_IAccessibleHypertext ||
-      guidService == IID_IAccessibleImage ||
-      guidService == IID_IAccessibleTable ||
-      guidService == IID_IAccessibleTable2 ||
-      guidService == IID_IAccessibleTableCell ||
-      guidService == IID_IAccessibleText ||
-      guidService == IID_IAccessibleValue ||
-      guidService == IID_ISimpleDOMDocument ||
-      guidService == IID_ISimpleDOMNode ||
-      guidService == IID_ISimpleDOMText ||
-      guidService == GUID_ISimpleDOM) {
+  if (riid == IID_IAccessible ||
+      riid == IID_IAccessible2 ||
+      riid == IID_IAccessibleAction ||
+      riid == IID_IAccessibleHyperlink ||
+      riid == IID_IAccessibleHypertext ||
+      riid == IID_IAccessibleImage ||
+      riid == IID_IAccessibleTable ||
+      riid == IID_IAccessibleTable2 ||
+      riid == IID_IAccessibleTableCell ||
+      riid == IID_IAccessibleText ||
+      riid == IID_IAccessibleValue ||
+      riid == IID_ISimpleDOMDocument ||
+      riid == IID_ISimpleDOMNode ||
+      riid == IID_ISimpleDOMText ||
+      riid == GUID_ISimpleDOM) {
+    return QueryInterface(riid, object);
+  }
+
+  // We only support the IAccessibleEx interface on Windows 8 and above. This
+  // is needed for the On screen Keyboard to show up in metro mode, when the

[dmazzoni, 2012/04/04 06:02:00]

Nit: On screen -> on-screen

[ananta, 2012/04/04 19:23:00]

Done.

+  // user taps an editable portion on the page.
+  // All methods in the IAccessibleEx interface are unimplemented.
+  if (riid == IID_IAccessibleEx &&
+      base::win::GetVersion() >= base::win::VERSION_WIN8) {
     return QueryInterface(riid, object);
   }
 
   *object = NULL;
   return E_FAIL;
 }
 
+STDMETHODIMP BrowserAccessibilityWin::GetPatternProvider(
+    PATTERNID id, IUnknown** provider) {
+  DVLOG(1) << "In Function: "
+           << __FUNCTION__
+           << " for pattern id: "
+           << id;
+  if (id == UIA_ValuePatternId || id == UIA_TextPatternId) {
+    if (IsEditableText()) {
+      DVLOG(1) << "Returning UIA text provider";
+      ui::UIATextProvider::CreateTextProvider(true, provider);
+      return S_OK;
+    }
+  }
+  return E_NOTIMPL;
+}
+
+STDMETHODIMP BrowserAccessibilityWin::GetPropertyValue(PROPERTYID id,
+                                                        VARIANT* ret) {

[dmazzoni, 2012/04/04 06:02:00]

Nit: indentation

[ananta, 2012/04/04 19:23:00]

Done.

+  DVLOG(1) << "In Function: "
+           << __FUNCTION__
+           << " for property id: "
+           << id;
+  V_VT(ret) = VT_EMPTY;
+  if (id == UIA_ControlTypePropertyId) {
+    if (IsEditableText()) {
+      V_VT(ret) = VT_I4;
+      ret->lVal = UIA_EditControlTypeId;
+      DVLOG(1) << "Returning Edit control type";
+    } else {
+      DVLOG(1) << "Returning empty control type";
+    }
+  }
+  return S_OK;
+}
+
 //
 // CComObjectRootEx methods.
 //
 
 HRESULT WINAPI BrowserAccessibilityWin::InternalQueryInterface(
     void* this_ptr,
     const _ATL_INTMAP_ENTRY* entries,
     REFIID iid,
     void** object) {
   if (iid == IID_IAccessibleImage) {
@@ skipping 775 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_;
 }