Add support for UIA accessibility interfaces like IAccessibleEx and IRawElementProviderSimple.

base/win/accessibility_misc_utils.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 "base/win/accessibility_misc_utils.h"
+
+#include "base/logging.h"
+
+namespace base {
+namespace win {
+
+// UIA TextProvider implementation.
+UIATextProvider::UIATextProvider()
+    : editable_(false) {}
+
+// static
+bool UIATextProvider::CreateTextProvider(bool editable, IUnknown** provider) {
+  CComObject<UIATextProvider>* text_provider = NULL;
+  HRESULT hr = CComObject<UIATextProvider>::CreateInstance(&text_provider);
+  if (SUCCEEDED(hr)) {
+    DCHECK(text_provider);
+    text_provider->set_editable(editable);
+    text_provider->AddRef();
+    *provider = static_cast<ITextProvider*>(text_provider);
+    return true;
+  }
+  return false;
+}
+
+STDMETHODIMP UIATextProvider::get_IsReadOnly(BOOL* read_only) {
+  *read_only = !editable_;
+  return S_OK;
+}
+
+}  // namespace win
+}  // namespace base