Add accessibility support for Textfields in Windows.

views/controls/textfield/native_textfield_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 "views/controls/textfield/native_textfield_win.h"
 
 #include <algorithm>
 
 #include "app/clipboard/clipboard.h"
 #include "app/clipboard/scoped_clipboard_writer.h"
 #include "app/l10n_util.h"
 #include "app/l10n_util_win.h"
 #include "app/win_util.h"
 #include "base/i18n/rtl.h"
 #include "base/keyboard_codes.h"
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
 #include "base/win_util.h"
 #include "gfx/native_theme_win.h"
 #include "grit/app_strings.h"
 #include "skia/ext/skia_utils_win.h"
+#include "views/controls/label.h"
 #include "views/controls/menu/menu_win.h"
 #include "views/controls/menu/menu_2.h"
 #include "views/controls/native/native_view_host.h"
 #include "views/controls/textfield/textfield.h"
 #include "views/focus/focus_manager.h"
 #include "views/focus/focus_util_win.h"
 #include "views/views_delegate.h"
 #include "views/widget/widget.h"
 
 namespace views {
@@ skipping 66 matching lines @@
   if (textfield_->style() & Textfield::STYLE_LOWERCASE) {
     DCHECK((textfield_->style() & Textfield::STYLE_PASSWORD) == 0);
     SetEditStyle(SES_LOWERCASE, SES_LOWERCASE);
   }
 
   // Set up the text_object_model_.
   ScopedComPtr<IRichEditOle, &IID_IRichEditOle> ole_interface;
   ole_interface.Attach(GetOleInterface());
   if (ole_interface)
     text_object_model_.QueryFrom(ole_interface);
+
+  InitializeAccessibilityInfo();
 }
 
 NativeTextfieldWin::~NativeTextfieldWin() {
   if (IsWindow())
     DestroyWindow();
 }
 
 void NativeTextfieldWin::AttachHack() {
   // See the code in textfield.cc that calls this for why this is here.
   container_view_->set_focus_view(textfield_);
@@ skipping 19 matching lines @@
 void NativeTextfieldWin::UpdateText() {
   std::wstring text = textfield_->text();
   // Adjusting the string direction before setting the text in order to make
   // sure both RTL and LTR strings are displayed properly.
   std::wstring text_to_set;
   if (!base::i18n::AdjustStringForLocaleDirection(text, &text_to_set))
     text_to_set = text;
   if (textfield_->style() & Textfield::STYLE_LOWERCASE)
     text_to_set = l10n_util::ToLower(text_to_set);
   SetWindowText(text_to_set.c_str());
+  UpdateAccessibleValue(text_to_set);
 }
 
 void NativeTextfieldWin::AppendText(const string16& text) {
   int text_length = GetWindowTextLength();
   ::SendMessage(m_hWnd, TBM_SETSEL, true, MAKELPARAM(text_length, text_length));
   ::SendMessage(m_hWnd, EM_REPLACESEL, false,
                 reinterpret_cast<LPARAM>(text.c_str()));
 }
 
 string16 NativeTextfieldWin::GetSelectedText() const {
@@ skipping 39 matching lines @@
     bg_color_ = skia::SkColorToCOLORREF(textfield_->background_color());
   } else {
     bg_color_ = GetSysColor(textfield_->read_only() ? COLOR_3DFACE
                                                     : COLOR_WINDOW);
   }
   CRichEditCtrl::SetBackgroundColor(bg_color_);
 }
 
 void NativeTextfieldWin::UpdateReadOnly() {
   SendMessage(m_hWnd, EM_SETREADONLY, textfield_->read_only(), 0);
+  UpdateAccessibleState(STATE_SYSTEM_READONLY, textfield_->read_only());
 }
 
 void NativeTextfieldWin::UpdateFont() {
   SendMessage(m_hWnd, WM_SETFONT,
               reinterpret_cast<WPARAM>(textfield_->font().hfont()), TRUE);
   // Setting the font blows away any text color we've set, so reset it.
   UpdateTextColor();
 }
 
 void NativeTextfieldWin::UpdateIsPassword() {
   // TODO: Need to implement for Windows.
+  UpdateAccessibleState(STATE_SYSTEM_PROTECTED, textfield_->IsPassword());
 }
 
 void NativeTextfieldWin::UpdateEnabled() {
   SendMessage(m_hWnd, WM_ENABLE, textfield_->IsEnabled(), 0);
+  UpdateAccessibleState(STATE_SYSTEM_UNAVAILABLE, !textfield_->IsEnabled());
 }
 
 gfx::Insets NativeTextfieldWin::CalculateInsets() {
   // NOTE: One would think GetThemeMargins would return the insets we should
   // use, but it doesn't. The margins returned by GetThemeMargins are always
   // 0.
 
   // This appears to be the insets used by Windows.
   return gfx::Insets(3, 3, 3, 3);
 }
@@ skipping 79 matching lines @@
     case IDS_APP_UNDO:       Undo();       break;
     case IDS_APP_CUT:        Cut();        break;
     case IDS_APP_COPY:       Copy();       break;
     case IDS_APP_PASTE:      Paste();      break;
     case IDS_APP_SELECT_ALL: SelectAll();  break;
     default:                 NOTREACHED(); break;
   }
   OnAfterPossibleChange();
 }
 
+void NativeTextfieldWin::InitializeAccessibilityInfo() {
+  // Set the accessible state.
+  accessibility_state_ = 0;
+
+  ScopedComPtr<IAccPropServices> pAccPropServices;
+  HRESULT hr = CoCreateInstance(CLSID_AccPropServices, NULL, CLSCTX_SERVER,
+      IID_IAccPropServices, reinterpret_cast<void**>(&pAccPropServices));
+  if (!SUCCEEDED(hr))
+    return;
+
+  VARIANT var;
+
+  // Set the accessible role.
+  var.vt = VT_I4;
+  var.lVal = ROLE_SYSTEM_TEXT;
+  hr = pAccPropServices->SetHwndProp(m_hWnd, OBJID_CLIENT,
+      CHILDID_SELF, PROPID_ACC_ROLE, var);
+
+  // Set the accessible name by getting the label text.
+  View* parent = textfield_->GetParent();
+  int label_index = parent->GetChildIndex(textfield_) - 1;
+  if (label_index  >= 0) {
+    std::wstring name;
+    View* label_view = parent->GetChildViewAt(label_index );
+    if (label_view ->GetClassName() == Label::kViewClassName &&

[Chris Guillory, 2010/06/15 17:30:16]

Can we DCHECK label_view ->GetClassName() == Label::kViewClassName?

+        label_view ->GetAccessibleName(&name)) {
+
+      hr = pAccPropServices->SetHwndPropStr(m_hWnd, OBJID_CLIENT,
+          CHILDID_SELF, PROPID_ACC_NAME, name.c_str());
+    }
+  }
+}
+
+void NativeTextfieldWin::UpdateAccessibleState(uint32 state_flag,
+                                               bool set_value) {
+  ScopedComPtr<IAccPropServices> pAccPropServices;
+  HRESULT hr = CoCreateInstance(CLSID_AccPropServices, NULL, CLSCTX_SERVER,
+      IID_IAccPropServices, reinterpret_cast<void**>(&pAccPropServices));
+  if (!SUCCEEDED(hr))
+    return;
+
+  VARIANT var;
+  var.vt = VT_I4;
+  var.lVal = set_value ? accessibility_state_ | state_flag
+      : accessibility_state_ & ~state_flag;
+  hr = pAccPropServices->SetHwndProp(m_hWnd, OBJID_CLIENT,
+      CHILDID_SELF, PROPID_ACC_STATE, var);
+
+  ::NotifyWinEvent(EVENT_OBJECT_STATECHANGE, m_hWnd, OBJID_CLIENT,
+                   CHILDID_SELF);
+}
+
+void NativeTextfieldWin::UpdateAccessibleValue(const std::wstring& value) {
+  ScopedComPtr<IAccPropServices> pAccPropServices;
+  HRESULT hr = CoCreateInstance(CLSID_AccPropServices, NULL, CLSCTX_SERVER,
+      IID_IAccPropServices, reinterpret_cast<void**>(&pAccPropServices));
+  if (!SUCCEEDED(hr))
+    return;
+
+  hr = pAccPropServices->SetHwndPropStr(m_hWnd, OBJID_CLIENT,
+      CHILDID_SELF, PROPID_ACC_VALUE, value.c_str());
+
+  ::NotifyWinEvent(EVENT_OBJECT_VALUECHANGE, m_hWnd, OBJID_CLIENT,
+                   CHILDID_SELF);
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // NativeTextfieldWin, private:
 
 void NativeTextfieldWin::OnChar(TCHAR ch, UINT repeat_count, UINT flags) {
   HandleKeystroke(GetCurrentMessage()->message, ch, repeat_count, flags);
 }
 
 void NativeTextfieldWin::OnContextMenu(HWND window, const POINT& point) {
   POINT p(point);
   if (point.x == -1 || point.y == -1) {
@@ skipping 496 matching lines @@
       // A string retrieved with a GetText() call contains a string being
       // composed by an IME. We remove the composition string from this search
       // string.
       new_text.erase(ime_composition_start_, ime_composition_length_);
       ime_composition_start_ = 0;
       ime_composition_length_ = 0;
       if (new_text.empty())
         return;
     }
     textfield_->SyncText();
+    UpdateAccessibleValue(textfield_->text());
     if (textfield_->GetController())
       textfield_->GetController()->ContentsChanged(textfield_, new_text);
   }
 }
 
 LONG NativeTextfieldWin::ClipXCoordToVisibleText(LONG x,
                                                  bool is_triple_click) const {
   // Clip the X coordinate to the left edge of the text.  Careful:
   // PosFromChar(0) may return a negative X coordinate if the beginning of the
   // text has scrolled off the edit, so don't go past the clip rect's edge.
@@ skipping 98 matching lines @@
 ////////////////////////////////////////////////////////////////////////////////
 // NativeTextfieldWrapper, public:
 
 // static
 NativeTextfieldWrapper* NativeTextfieldWrapper::CreateWrapper(
     Textfield* field) {
   return new NativeTextfieldWin(field);
 }
 
 }  // namespace views