views: [accessibility] Add support for Accessibility Value.

BUG=9604
TEST=point AccExplorer to Edit Bookmark dialog, see if everything has a MSAA information, like: Name, Role, State, Value.

Patch from Thiago Farina <thiago.farina@gmail.com>
Review URL: http://codereview.chromium.org/928001

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@42831 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 34 insertions, 7 deletions

diff --git a/views/accessibility/view_accessibility.cc b/views/accessibility/view_accessibility.cc
index f8bf516..32239d1 100644
--- a/views/accessibility/view_accessibility.cc
+++ b/views/accessibility/view_accessibility.cc
@@ -479,7 +479,7 @@ STDMETHODIMP ViewAccessibility::get_accName(VARIANT var_id, BSTR* name) {
   std::wstring temp_name;
 
   if (var_id.lVal == CHILDID_SELF) {
-    // Retrieve the parent view's name.
+    // Retrieve the current view's name.
     view_->GetAccessibleName(&temp_name);
   } else {
     if (!IsValidChild((var_id.lVal - 1), view_)) {
@@ -600,6 +600,39 @@ STDMETHODIMP ViewAccessibility::get_accState(VARIANT var_id, VARIANT* state) {
   return S_OK;
 }
 
+STDMETHODIMP ViewAccessibility::get_accValue(VARIANT var_id, BSTR* value) {
+  if (var_id.vt != VT_I4 || !value) {
+    return E_INVALIDARG;
+  }
+
+  if (!view_) {
+    return E_FAIL;
+  }
+
+  std::wstring temp_value;
+
+  if (var_id.lVal == CHILDID_SELF) {
+    // Retrieve the current view's value.
+    view_->GetAccessibleValue(&temp_value);
+  } else {
+    if (!IsValidChild((var_id.lVal - 1), view_)) {
+      return E_INVALIDARG;
+    }
+    // Retrieve the child view's value.
+    view_->GetChildViewAt(var_id.lVal - 1)->GetAccessibleValue(&temp_value);
+  }
+  if (!temp_value.empty()) {
+    // Return value retrieved.
+    *value = SysAllocString(temp_value.c_str());
+  } else {
+    // If view has no value, fall back into the default implementation.
+    *value = NULL;
+    return E_NOTIMPL;
+  }
+
+  return S_OK;
+}
+
 // Helper functions.
 
 bool ViewAccessibility::IsValidChild(int child_id, views::View* view) const {
@@ -725,12 +758,6 @@ HRESULT ViewAccessibility::accDoDefaultAction(VARIANT var_id) {
   return E_NOTIMPL;
 }
 
-STDMETHODIMP ViewAccessibility::get_accValue(VARIANT var_id, BSTR* value) {
-  if (value)
-    *value = NULL;
-  return E_NOTIMPL;
-}
-
 STDMETHODIMP ViewAccessibility::get_accSelection(VARIANT* selected) {
   if (selected)
     selected->vt = VT_EMPTY;