ui/views/accessibility/native_view_accessibility_win.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "ui/views/accessibility/native_view_accessibility_win.h"
   6
   7 #include <oleacc.h>
   8 #include <UIAutomationClient.h>
   9
  10 #include <set>
  11 #include <vector>
  12
  13 #include "base/memory/singleton.h"
  14 #include "base/strings/utf_string_conversions.h"
  15 #include "base/win/scoped_comptr.h"
  16 #include "base/win/windows_version.h"
  17 #include "third_party/iaccessible2/ia2_api_all.h"
  18 #include "ui/accessibility/ax_enums.h"
  19 #include "ui/accessibility/ax_text_utils.h"
  20 #include "ui/accessibility/ax_view_state.h"
  21 #include "ui/base/win/accessibility_ids_win.h"
  22 #include "ui/base/win/accessibility_misc_utils.h"
  23 #include "ui/base/win/atl_module.h"
  24 #include "ui/views/controls/button/custom_button.h"
  25 #include "ui/views/focus/focus_manager.h"
  26 #include "ui/views/focus/view_storage.h"
  27 #include "ui/views/widget/widget.h"
  28 #include "ui/views/win/hwnd_util.h"
  29
  30 namespace views {
  31 namespace {
  32
  33 class AccessibleWebViewRegistry {
  34  public:
  35   static AccessibleWebViewRegistry* GetInstance();
  36
  37   void RegisterWebView(View* web_view);
  38
  39   void UnregisterWebView(View* web_view);
  40
  41   // Given the view that received the request for the accessible
  42   // id in |top_view|, and the child id requested, return the native
  43   // accessible object with that child id from one of the WebViews in
  44   // |top_view|'s view hierarchy, if any.
  45   IAccessible* GetAccessibleFromWebView(View* top_view, long child_id);
  46
  47   // The system uses IAccessible APIs for many purposes, but only
  48   // assistive technology like screen readers uses IAccessible2.
  49   // Call this method to note that the IAccessible2 interface was queried and
  50   // that WebViews should be proactively notified that this interface will be
  51   // used. If this is enabled for the first time, this will explicitly call
  52   // QueryService with an argument of IAccessible2 on all WebViews, otherwise
  53   // it will just do it from now on.
  54   void EnableIAccessible2Support();
  55
  56  private:
  57   friend struct DefaultSingletonTraits<AccessibleWebViewRegistry>;
  58   AccessibleWebViewRegistry();
  59   ~AccessibleWebViewRegistry() {}
  60
  61   IAccessible* AccessibleObjectFromChildId(View* web_view, long child_id);
  62
  63   void QueryIAccessible2Interface(View* web_view);
  64
  65   // Set of all web views. We check whether each one is contained in a
  66   // top view dynamically rather than keeping track of a map.
  67   std::set<View*> web_views_;
  68
  69   // The most recent top view used in a call to GetAccessibleFromWebView.
  70   View* last_top_view_;
  71
  72   // The most recent web view where an accessible object was found,
  73   // corresponding to |last_top_view_|.
  74   View* last_web_view_;
  75
  76   // If IAccessible2 support is enabled, we query the IAccessible2 interface
  77   // of WebViews proactively when they're registered, so that they are
  78   // aware that they need to support this interface.
  79   bool iaccessible2_support_enabled_;
  80
  81   DISALLOW_COPY_AND_ASSIGN(AccessibleWebViewRegistry);
  82 };
  83
  84 AccessibleWebViewRegistry::AccessibleWebViewRegistry()
  85     : last_top_view_(NULL),
  86       last_web_view_(NULL),
  87       iaccessible2_support_enabled_(false) {
  88 }
  89
  90 AccessibleWebViewRegistry* AccessibleWebViewRegistry::GetInstance() {
  91   return Singleton<AccessibleWebViewRegistry>::get();
  92 }
  93
  94 void AccessibleWebViewRegistry::RegisterWebView(View* web_view) {
  95   DCHECK(web_views_.find(web_view) == web_views_.end());
  96   web_views_.insert(web_view);
  97
  98   if (iaccessible2_support_enabled_)
  99     QueryIAccessible2Interface(web_view);
 100 }
 101
 102 void AccessibleWebViewRegistry::UnregisterWebView(View* web_view) {
 103   DCHECK(web_views_.find(web_view) != web_views_.end());
 104   web_views_.erase(web_view);
 105   if (last_web_view_ == web_view) {
 106     last_top_view_ = NULL;
 107     last_web_view_ = NULL;
 108   }
 109 }
 110
 111 IAccessible* AccessibleWebViewRegistry::GetAccessibleFromWebView(
 112     View* top_view, long child_id) {
 113   // This function gets called frequently, so try to avoid searching all
 114   // of the web views if the notification is on the same web view that
 115   // sent the last one.
 116   if (last_top_view_ == top_view) {
 117     IAccessible* accessible =
 118         AccessibleObjectFromChildId(last_web_view_, child_id);
 119     if (accessible)
 120       return accessible;
 121   }
 122
 123   // Search all web views. For each one, first ensure it's a descendant
 124   // of this view where the event was posted - and if so, see if it owns
 125   // an accessible object with that child id. If so, save the view to speed
 126   // up the next notification.
 127   for (std::set<View*>::iterator iter = web_views_.begin();
 128        iter != web_views_.end(); ++iter) {
 129     View* web_view = *iter;
 130     if (top_view == web_view || !top_view->Contains(web_view))
 131       continue;
 132     IAccessible* accessible = AccessibleObjectFromChildId(web_view, child_id);
 133     if (accessible) {
 134       last_top_view_ = top_view;
 135       last_web_view_ = web_view;
 136       return accessible;
 137     }
 138   }
 139
 140   return NULL;
 141 }
 142
 143 void AccessibleWebViewRegistry::EnableIAccessible2Support() {
 144   if (iaccessible2_support_enabled_)
 145     return;
 146   iaccessible2_support_enabled_ = true;
 147   for (std::set<View*>::iterator iter = web_views_.begin();
 148        iter != web_views_.end(); ++iter) {
 149     QueryIAccessible2Interface(*iter);
 150   }
 151 }
 152
 153 IAccessible* AccessibleWebViewRegistry::AccessibleObjectFromChildId(
 154     View* web_view,
 155     long child_id) {
 156   IAccessible* web_view_accessible = web_view->GetNativeViewAccessible();
 157   if (web_view_accessible == NULL)
 158     return NULL;
 159
 160   VARIANT var_child;
 161   var_child.vt = VT_I4;
 162   var_child.lVal = child_id;
 163   IAccessible* result = NULL;
 164   if (S_OK == web_view_accessible->get_accChild(
 165       var_child, reinterpret_cast<IDispatch**>(&result))) {
 166     return result;
 167   }
 168
 169   return NULL;
 170 }
 171
 172 void AccessibleWebViewRegistry::QueryIAccessible2Interface(View* web_view) {
 173   IAccessible* web_view_accessible = web_view->GetNativeViewAccessible();
 174   if (!web_view_accessible)
 175     return;
 176
 177   base::win::ScopedComPtr<IServiceProvider> service_provider;
 178   if (S_OK != web_view_accessible->QueryInterface(service_provider.Receive()))
 179     return;
 180   base::win::ScopedComPtr<IAccessible2> iaccessible2;
 181   service_provider->QueryService(
 182       IID_IAccessible, IID_IAccessible2,
 183       reinterpret_cast<void**>(iaccessible2.Receive()));
 184 }
 185
 186 }  // anonymous namespace
 187
 188 // static
 189 long NativeViewAccessibilityWin::next_unique_id_ = 1;
 190 int NativeViewAccessibilityWin::view_storage_ids_[kMaxViewStorageIds] = {0};
 191 int NativeViewAccessibilityWin::next_view_storage_id_index_ = 0;
 192 std::vector<int> NativeViewAccessibilityWin::alert_target_view_storage_ids_;
 193
 194 // static
 195 NativeViewAccessibility* NativeViewAccessibility::Create(View* view) {
 196   // Make sure ATL is initialized in this module.
 197   ui::win::CreateATLModuleIfNeeded();
 198
 199   CComObject<NativeViewAccessibilityWin>* instance = NULL;
 200   HRESULT hr = CComObject<NativeViewAccessibilityWin>::CreateInstance(
 201       &instance);
 202   DCHECK(SUCCEEDED(hr));
 203   instance->set_view(view);
 204   instance->AddRef();
 205   return instance;
 206 }
 207
 208 NativeViewAccessibilityWin::NativeViewAccessibilityWin()
 209     : unique_id_(next_unique_id_++) {
 210 }
 211
 212 NativeViewAccessibilityWin::~NativeViewAccessibilityWin() {
 213   RemoveAlertTarget();
 214 }
 215
 216 void NativeViewAccessibilityWin::NotifyAccessibilityEvent(
 217     ui::AXEvent event_type) {
 218   if (!view_)
 219     return;
 220
 221   ViewStorage* view_storage = ViewStorage::GetInstance();
 222   HWND hwnd = HWNDForView(view_);
 223   int view_storage_id = view_storage_ids_[next_view_storage_id_index_];
 224   if (view_storage_id == 0) {
 225     view_storage_id = view_storage->CreateStorageID();
 226     view_storage_ids_[next_view_storage_id_index_] = view_storage_id;
 227   } else {
 228     view_storage->RemoveView(view_storage_id);
 229   }
 230   view_storage->StoreView(view_storage_id, view_);
 231
 232   // Positive child ids are used for enumerating direct children,
 233   // negative child ids can be used as unique ids to refer to a specific
 234   // descendants.  Make index into view_storage_ids_ into a negative child id.
 235   int child_id =
 236       base::win::kFirstViewsAccessibilityId - next_view_storage_id_index_;
 237   ::NotifyWinEvent(MSAAEvent(event_type), hwnd, OBJID_CLIENT, child_id);
 238   next_view_storage_id_index_ =
 239       (next_view_storage_id_index_ + 1) % kMaxViewStorageIds;
 240
 241   // Keep track of views that are a target of an alert event.
 242   if (event_type == ui::AX_EVENT_ALERT)
 243     AddAlertTarget();
 244 }
 245
 246 gfx::NativeViewAccessible NativeViewAccessibilityWin::GetNativeObject() {
 247   return this;
 248 }
 249
 250 void NativeViewAccessibilityWin::Destroy() {
 251   view_ = NULL;
 252   Release();
 253 }
 254
 255 STDMETHODIMP NativeViewAccessibilityWin::accHitTest(
 256     LONG x_left, LONG y_top, VARIANT* child) {
 257   if (!child)
 258     return E_INVALIDARG;
 259
 260   if (!view_ || !view_->GetWidget())
 261     return E_FAIL;
 262
 263   // If this is a root view, our widget might have child widgets.
 264   // Search child widgets first, since they're on top in the z-order.
 265   if (view_->GetWidget()->GetRootView() == view_) {
 266     std::vector<Widget*> child_widgets;
 267     PopulateChildWidgetVector(&child_widgets);
 268     for (size_t i = 0; i < child_widgets.size(); ++i) {
 269       Widget* child_widget = child_widgets[i];
 270       IAccessible* child_accessible =
 271           child_widget->GetRootView()->GetNativeViewAccessible();
 272       HRESULT result = child_accessible->accHitTest(x_left, y_top, child);
 273       if (result == S_OK)
 274         return result;
 275     }
 276   }
 277
 278   gfx::Point point(x_left, y_top);
 279   View::ConvertPointFromScreen(view_, &point);
 280
 281   // If the point is not inside this view, return false.
 282   if (!view_->HitTestPoint(point)) {
 283     child->vt = VT_EMPTY;
 284     return S_FALSE;
 285   }
 286
 287   // Check if the point is within any of the immediate children of this
 288   // view.
 289   View* hit_child_view = NULL;
 290   for (int i = view_->child_count() - 1; i >= 0; --i) {
 291     View* child_view = view_->child_at(i);
 292     if (!child_view->visible())
 293       continue;
 294
 295     gfx::Point point_in_child_coords(point);
 296     view_->ConvertPointToTarget(view_, child_view, &point_in_child_coords);
 297     if (child_view->HitTestPoint(point_in_child_coords)) {
 298       hit_child_view = child_view;
 299       break;
 300     }
 301   }
 302
 303   // If the point was within one of this view's immediate children,
 304   // call accHitTest recursively on that child's native view accessible -
 305   // which may be a recursive call to this function or it may be overridden,
 306   // for example in the case of a WebView.
 307   if (hit_child_view) {
 308     HRESULT result = hit_child_view->GetNativeViewAccessible()->accHitTest(
 309         x_left, y_top, child);
 310
 311     // If the recursive call returned CHILDID_SELF, we have to convert that
 312     // into a VT_DISPATCH for the return value to this call.
 313     if (S_OK == result && child->vt == VT_I4 && child->lVal == CHILDID_SELF) {
 314       child->vt = VT_DISPATCH;
 315       child->pdispVal = hit_child_view->GetNativeViewAccessible();
 316       // Always increment ref when returning a reference to a COM object.
 317       child->pdispVal->AddRef();
 318     }
 319     return result;
 320   }
 321
 322   // This object is the best match, so return CHILDID_SELF. It's tempting to
 323   // simplify the logic and use VT_DISPATCH everywhere, but the Windows
 324   // call AccessibleObjectFromPoint will keep calling accHitTest until some
 325   // object returns CHILDID_SELF.
 326   child->vt = VT_I4;
 327   child->lVal = CHILDID_SELF;
 328   return S_OK;
 329 }
 330
 331 HRESULT NativeViewAccessibilityWin::accDoDefaultAction(VARIANT var_id) {
 332   if (!IsValidId(var_id))
 333     return E_INVALIDARG;
 334
 335   // The object does not support the method. This value is returned for
 336   // controls that do not perform actions, such as edit fields.
 337   return DISP_E_MEMBERNOTFOUND;
 338 }
 339
 340 STDMETHODIMP NativeViewAccessibilityWin::accLocation(
 341     LONG* x_left, LONG* y_top, LONG* width, LONG* height, VARIANT var_id) {
 342   if (!IsValidId(var_id) || !x_left || !y_top || !width || !height)
 343     return E_INVALIDARG;
 344
 345   if (!view_)
 346     return E_FAIL;
 347
 348   if (!view_->bounds().IsEmpty()) {
 349     *width  = view_->width();
 350     *height = view_->height();
 351     gfx::Point topleft(view_->bounds().origin());
 352     View::ConvertPointToScreen(
 353         view_->parent() ? view_->parent() : view_, &topleft);
 354     *x_left = topleft.x();
 355     *y_top  = topleft.y();
 356   } else {
 357     return E_FAIL;
 358   }
 359   return S_OK;
 360 }
 361
 362 STDMETHODIMP NativeViewAccessibilityWin::accNavigate(
 363     LONG nav_dir, VARIANT start, VARIANT* end) {
 364   if (start.vt != VT_I4 || !end)
 365     return E_INVALIDARG;
 366
 367   if (!view_)
 368     return E_FAIL;
 369
 370   switch (nav_dir) {
 371     case NAVDIR_FIRSTCHILD:
 372     case NAVDIR_LASTCHILD: {
 373       if (start.lVal != CHILDID_SELF) {
 374         // Start of navigation must be on the View itself.
 375         return E_INVALIDARG;
 376       } else if (!view_->has_children()) {
 377         // No children found.
 378         return S_FALSE;
 379       }
 380
 381       // Set child_id based on first or last child.
 382       int child_id = 0;
 383       if (nav_dir == NAVDIR_LASTCHILD)
 384         child_id = view_->child_count() - 1;
 385
 386       View* child = view_->child_at(child_id);
 387       end->vt = VT_DISPATCH;
 388       end->pdispVal = child->GetNativeViewAccessible();
 389       end->pdispVal->AddRef();
 390       return S_OK;
 391     }
 392     case NAVDIR_LEFT:
 393     case NAVDIR_UP:
 394     case NAVDIR_PREVIOUS:
 395     case NAVDIR_RIGHT:
 396     case NAVDIR_DOWN:
 397     case NAVDIR_NEXT: {
 398       // Retrieve parent to access view index and perform bounds checking.
 399       View* parent = view_->parent();
 400       if (!parent) {
 401         return E_FAIL;
 402       }
 403
 404       if (start.lVal == CHILDID_SELF) {
 405         int view_index = parent->GetIndexOf(view_);
 406         // Check navigation bounds, adjusting for View child indexing (MSAA
 407         // child indexing starts with 1, whereas View indexing starts with 0).
 408         if (!IsValidNav(nav_dir, view_index, -1,
 409                         parent->child_count() - 1)) {
 410           // Navigation attempted to go out-of-bounds.
 411           end->vt = VT_EMPTY;
 412           return S_FALSE;
 413         } else {
 414           if (IsNavDirNext(nav_dir)) {
 415             view_index += 1;
 416           } else {
 417             view_index -=1;
 418           }
 419         }
 420
 421         View* child = parent->child_at(view_index);
 422         end->pdispVal = child->GetNativeViewAccessible();
 423         end->vt = VT_DISPATCH;
 424         end->pdispVal->AddRef();
 425         return S_OK;
 426       } else {
 427         // Check navigation bounds, adjusting for MSAA child indexing (MSAA
 428         // child indexing starts with 1, whereas View indexing starts with 0).
 429         if (!IsValidNav(nav_dir, start.lVal, 0, parent->child_count() + 1)) {
 430             // Navigation attempted to go out-of-bounds.
 431             end->vt = VT_EMPTY;
 432             return S_FALSE;
 433           } else {
 434             if (IsNavDirNext(nav_dir)) {
 435               start.lVal += 1;
 436             } else {
 437               start.lVal -= 1;
 438             }
 439         }
 440
 441         HRESULT result = this->get_accChild(start, &end->pdispVal);
 442         if (result == S_FALSE) {
 443           // Child is a leaf.
 444           end->vt = VT_I4;
 445           end->lVal = start.lVal;
 446         } else if (result == E_INVALIDARG) {
 447           return E_INVALIDARG;
 448         } else {
 449           // Child is not a leaf.
 450           end->vt = VT_DISPATCH;
 451         }
 452       }
 453       break;
 454     }
 455     default:
 456       return E_INVALIDARG;
 457   }
 458   // Navigation performed correctly. Global return for this function, if no
 459   // error triggered an escape earlier.
 460   return S_OK;
 461 }
 462
 463 STDMETHODIMP NativeViewAccessibilityWin::get_accChild(VARIANT var_child,
 464                                                       IDispatch** disp_child) {
 465   if (var_child.vt != VT_I4 || !disp_child)
 466     return E_INVALIDARG;
 467
 468   if (!view_ || !view_->GetWidget())
 469     return E_FAIL;
 470
 471   LONG child_id = V_I4(&var_child);
 472
 473   if (child_id == CHILDID_SELF) {
 474     // Remain with the same dispatch.
 475     return S_OK;
 476   }
 477
 478   // If this is a root view, our widget might have child widgets. Include
 479   std::vector<Widget*> child_widgets;
 480   if (view_->GetWidget()->GetRootView() == view_)
 481     PopulateChildWidgetVector(&child_widgets);
 482   int child_widget_count = static_cast<int>(child_widgets.size());
 483
 484   View* child_view = NULL;
 485   if (child_id > 0) {
 486     // Positive child ids are a 1-based child index, used by clients
 487     // that want to enumerate all immediate children.
 488     int child_id_as_index = child_id - 1;
 489     if (child_id_as_index < view_->child_count()) {
 490       child_view = view_->child_at(child_id_as_index);
 491     } else if (child_id_as_index < view_->child_count() + child_widget_count) {
 492       Widget* child_widget =
 493           child_widgets[child_id_as_index - view_->child_count()];
 494       child_view = child_widget->GetRootView();
 495     }
 496   } else {
 497     // Negative child ids can be used to map to any descendant.
 498     // Check child widget first.
 499     for (int i = 0; i < child_widget_count; i++) {
 500       Widget* child_widget = child_widgets[i];
 501       IAccessible* child_accessible =
 502           child_widget->GetRootView()->GetNativeViewAccessible();
 503       HRESULT result = child_accessible->get_accChild(var_child, disp_child);
 504       if (result == S_OK)
 505         return result;
 506     }
 507
 508     // We map child ids to a view storage id that can refer to a
 509     // specific view (if that view still exists).
 510     int view_storage_id_index =
 511         base::win::kFirstViewsAccessibilityId - child_id;
 512     if (view_storage_id_index >= 0 &&
 513         view_storage_id_index < kMaxViewStorageIds) {
 514       int view_storage_id = view_storage_ids_[view_storage_id_index];
 515       ViewStorage* view_storage = ViewStorage::GetInstance();
 516       child_view = view_storage->RetrieveView(view_storage_id);
 517     } else {
 518       *disp_child = AccessibleWebViewRegistry::GetInstance()->
 519           GetAccessibleFromWebView(view_, child_id);
 520       if (*disp_child)
 521         return S_OK;
 522     }
 523   }
 524
 525   if (!child_view) {
 526     // No child found.
 527     *disp_child = NULL;
 528     return E_FAIL;
 529   }
 530
 531   *disp_child = child_view->GetNativeViewAccessible();
 532   if (*disp_child) {
 533     (*disp_child)->AddRef();
 534     return S_OK;
 535   }
 536
 537   return E_FAIL;
 538 }
 539
 540 STDMETHODIMP NativeViewAccessibilityWin::get_accChildCount(LONG* child_count) {
 541   if (!child_count)
 542     return E_INVALIDARG;
 543
 544   if (!view_ || !view_->GetWidget())
 545     return E_FAIL;
 546
 547   *child_count = view_->child_count();
 548
 549   // If this is a root view, our widget might have child widgets. Include
 550   // them, too.
 551   if (view_->GetWidget()->GetRootView() == view_) {
 552     std::vector<Widget*> child_widgets;
 553     PopulateChildWidgetVector(&child_widgets);
 554     *child_count += child_widgets.size();
 555   }
 556
 557   return S_OK;
 558 }
 559
 560 STDMETHODIMP NativeViewAccessibilityWin::get_accDefaultAction(
 561     VARIANT var_id, BSTR* def_action) {
 562   if (!IsValidId(var_id) || !def_action)
 563     return E_INVALIDARG;
 564
 565   if (!view_)
 566     return E_FAIL;
 567
 568   ui::AXViewState state;
 569   view_->GetAccessibleState(&state);
 570   base::string16 temp_action = state.default_action;
 571
 572   if (!temp_action.empty()) {
 573     *def_action = SysAllocString(temp_action.c_str());
 574   } else {
 575     return S_FALSE;
 576   }
 577
 578   return S_OK;
 579 }
 580
 581 STDMETHODIMP NativeViewAccessibilityWin::get_accDescription(
 582     VARIANT var_id, BSTR* desc) {
 583   if (!IsValidId(var_id) || !desc)
 584     return E_INVALIDARG;
 585
 586   if (!view_)
 587     return E_FAIL;
 588
 589   base::string16 temp_desc;
 590
 591   view_->GetTooltipText(gfx::Point(), &temp_desc);
 592   if (!temp_desc.empty()) {
 593     *desc = SysAllocString(temp_desc.c_str());
 594   } else {
 595     return S_FALSE;
 596   }
 597
 598   return S_OK;
 599 }
 600
 601 STDMETHODIMP NativeViewAccessibilityWin::get_accFocus(VARIANT* focus_child) {
 602   if (!focus_child)
 603     return E_INVALIDARG;
 604
 605   if (!view_)
 606     return E_FAIL;
 607
 608   FocusManager* focus_manager = view_->GetFocusManager();
 609   View* focus = focus_manager ? focus_manager->GetFocusedView() : NULL;
 610   if (focus == view_) {
 611     // This view has focus.
 612     focus_child->vt = VT_I4;
 613     focus_child->lVal = CHILDID_SELF;
 614   } else if (focus && view_->Contains(focus)) {
 615     // Return the child object that has the keyboard focus.
 616     focus_child->vt = VT_DISPATCH;
 617     focus_child->pdispVal = focus->GetNativeViewAccessible();
 618     focus_child->pdispVal->AddRef();
 619     return S_OK;
 620   } else {
 621     // Neither this object nor any of its children has the keyboard focus.
 622     focus_child->vt = VT_EMPTY;
 623   }
 624   return S_OK;
 625 }
 626
 627 STDMETHODIMP NativeViewAccessibilityWin::get_accKeyboardShortcut(
 628     VARIANT var_id, BSTR* acc_key) {
 629   if (!IsValidId(var_id) || !acc_key)
 630     return E_INVALIDARG;
 631
 632   if (!view_)
 633     return E_FAIL;
 634
 635   ui::AXViewState state;
 636   view_->GetAccessibleState(&state);
 637   base::string16 temp_key = state.keyboard_shortcut;
 638
 639   if (!temp_key.empty()) {
 640     *acc_key = SysAllocString(temp_key.c_str());
 641   } else {
 642     return S_FALSE;
 643   }
 644
 645   return S_OK;
 646 }
 647
 648 STDMETHODIMP NativeViewAccessibilityWin::get_accName(
 649     VARIANT var_id, BSTR* name) {
 650   if (!IsValidId(var_id) || !name)
 651     return E_INVALIDARG;
 652
 653   if (!view_)
 654     return E_FAIL;
 655
 656   // Retrieve the current view's name.
 657   ui::AXViewState state;
 658   view_->GetAccessibleState(&state);
 659   base::string16 temp_name = state.name;
 660   if (!temp_name.empty()) {
 661     // Return name retrieved.
 662     *name = SysAllocString(temp_name.c_str());
 663   } else {
 664     // If view has no name, return S_FALSE.
 665     return S_FALSE;
 666   }
 667
 668   return S_OK;
 669 }
 670
 671 STDMETHODIMP NativeViewAccessibilityWin::get_accParent(
 672     IDispatch** disp_parent) {
 673   if (!disp_parent)
 674     return E_INVALIDARG;
 675
 676   if (!view_)
 677     return E_FAIL;
 678
 679   *disp_parent = NULL;
 680   View* parent_view = view_->parent();
 681
 682   if (!parent_view) {
 683     HWND hwnd = HWNDForView(view_);
 684     if (!hwnd)
 685       return S_FALSE;
 686
 687     return ::AccessibleObjectFromWindow(
 688         hwnd, OBJID_WINDOW, IID_IAccessible,
 689         reinterpret_cast<void**>(disp_parent));
 690   }
 691
 692   *disp_parent = parent_view->GetNativeViewAccessible();
 693   (*disp_parent)->AddRef();
 694   return S_OK;
 695 }
 696
 697 STDMETHODIMP NativeViewAccessibilityWin::get_accRole(
 698     VARIANT var_id, VARIANT* role) {
 699   if (!IsValidId(var_id) || !role)
 700     return E_INVALIDARG;
 701
 702   if (!view_)
 703     return E_FAIL;
 704
 705   ui::AXViewState state;
 706   view_->GetAccessibleState(&state);
 707   role->vt = VT_I4;
 708   role->lVal = MSAARole(state.role);
 709   return S_OK;
 710 }
 711
 712 STDMETHODIMP NativeViewAccessibilityWin::get_accState(
 713     VARIANT var_id, VARIANT* state) {
 714   // This returns MSAA states. See also the IAccessible2 interface
 715   // get_states().
 716
 717   if (!IsValidId(var_id) || !state)
 718     return E_INVALIDARG;
 719
 720   if (!view_)
 721     return E_FAIL;
 722
 723   state->vt = VT_I4;
 724
 725   // Retrieve all currently applicable states of the parent.
 726   SetState(state, view_);
 727
 728   // Make sure that state is not empty, and has the proper type.
 729   if (state->vt == VT_EMPTY)
 730     return E_FAIL;
 731
 732   return S_OK;
 733 }
 734
 735 STDMETHODIMP NativeViewAccessibilityWin::get_accValue(VARIANT var_id,
 736                                                       BSTR* value) {
 737   if (!IsValidId(var_id) || !value)
 738     return E_INVALIDARG;
 739
 740   if (!view_)
 741     return E_FAIL;
 742
 743   // Retrieve the current view's value.
 744   ui::AXViewState state;
 745   view_->GetAccessibleState(&state);
 746   base::string16 temp_value = state.value;
 747
 748   if (!temp_value.empty()) {
 749     // Return value retrieved.
 750     *value = SysAllocString(temp_value.c_str());
 751   } else {
 752     // If view has no value, fall back into the default implementation.
 753     *value = NULL;
 754     return E_NOTIMPL;
 755   }
 756
 757   return S_OK;
 758 }
 759
 760 STDMETHODIMP NativeViewAccessibilityWin::put_accValue(VARIANT var_id,
 761                                                       BSTR new_value) {
 762   if (!IsValidId(var_id) || !new_value)
 763     return E_INVALIDARG;
 764
 765   if (!view_)
 766     return E_FAIL;
 767
 768   // Return an error if the view can't set the value.
 769   ui::AXViewState state;
 770   view_->GetAccessibleState(&state);
 771   if (state.set_value_callback.is_null())
 772     return E_FAIL;
 773
 774   state.set_value_callback.Run(new_value);
 775   return S_OK;
 776 }
 777
 778 // IAccessible functions not supported.
 779
 780 STDMETHODIMP NativeViewAccessibilityWin::get_accSelection(VARIANT* selected) {
 781   if (selected)
 782     selected->vt = VT_EMPTY;
 783   return E_NOTIMPL;
 784 }
 785
 786 STDMETHODIMP NativeViewAccessibilityWin::accSelect(
 787     LONG flagsSelect, VARIANT var_id) {
 788   return E_NOTIMPL;
 789 }
 790
 791 STDMETHODIMP NativeViewAccessibilityWin::get_accHelp(
 792     VARIANT var_id, BSTR* help) {
 793   base::string16 temp = base::UTF8ToUTF16(view_->GetClassName());
 794   *help = SysAllocString(temp.c_str());
 795   return S_OK;
 796 }
 797
 798 STDMETHODIMP NativeViewAccessibilityWin::get_accHelpTopic(
 799     BSTR* help_file, VARIANT var_id, LONG* topic_id) {
 800   if (help_file) {
 801     *help_file = NULL;
 802   }
 803   if (topic_id) {
 804     *topic_id = static_cast<LONG>(-1);
 805   }
 806   return E_NOTIMPL;
 807 }
 808
 809 STDMETHODIMP NativeViewAccessibilityWin::put_accName(
 810     VARIANT var_id, BSTR put_name) {
 811   // Deprecated.
 812   return E_NOTIMPL;
 813 }
 814
 815 //
 816 // IAccessible2
 817 //
 818
 819 STDMETHODIMP NativeViewAccessibilityWin::role(LONG* role) {
 820   if (!view_)
 821     return E_FAIL;
 822
 823   if (!role)
 824     return E_INVALIDARG;
 825
 826   ui::AXViewState state;
 827   view_->GetAccessibleState(&state);
 828   *role = MSAARole(state.role);
 829   return S_OK;
 830 }
 831
 832 STDMETHODIMP NativeViewAccessibilityWin::get_states(AccessibleStates* states) {
 833   // This returns IAccessible2 states, which supplement MSAA states.
 834   // See also the MSAA interface get_accState.
 835
 836   if (!view_)
 837     return E_FAIL;
 838
 839   if (!states)
 840     return E_INVALIDARG;
 841
 842   ui::AXViewState state;
 843   view_->GetAccessibleState(&state);
 844
 845   // There are only a couple of states we need to support
 846   // in IAccessible2. If any more are added, we may want to
 847   // add a helper function like MSAAState.
 848   *states = IA2_STATE_OPAQUE;
 849   if (state.HasStateFlag(ui::AX_STATE_EDITABLE))
 850     *states |= IA2_STATE_EDITABLE;
 851
 852   return S_OK;
 853 }
 854
 855 STDMETHODIMP NativeViewAccessibilityWin::get_uniqueID(LONG* unique_id) {
 856   if (!view_)
 857     return E_FAIL;
 858
 859   if (!unique_id)
 860     return E_INVALIDARG;
 861
 862   *unique_id = unique_id_;
 863   return S_OK;
 864 }
 865
 866 STDMETHODIMP NativeViewAccessibilityWin::get_windowHandle(HWND* window_handle) {
 867   if (!view_)
 868     return E_FAIL;
 869
 870   if (!window_handle)
 871     return E_INVALIDARG;
 872
 873   *window_handle = HWNDForView(view_);
 874   return *window_handle ? S_OK : S_FALSE;
 875 }
 876
 877 STDMETHODIMP NativeViewAccessibilityWin::get_relationTargetsOfType(
 878     BSTR type_bstr,
 879     long max_targets,
 880     IUnknown ***targets,
 881     long *n_targets) {
 882   if (!view_)
 883     return E_FAIL;
 884
 885   if (!targets || !n_targets)
 886     return E_INVALIDARG;
 887
 888   *n_targets = 0;
 889   *targets = NULL;
 890
 891   // Only respond to requests for relations of type "alerts" on the
 892   // root view.
 893   base::string16 type(type_bstr);
 894   if (type != L"alerts" || view_->parent())
 895     return S_FALSE;
 896
 897   // Collect all of the alert views that are still valid.
 898   std::vector<View*> alert_views;
 899   ViewStorage* view_storage = ViewStorage::GetInstance();
 900   for (size_t i = 0; i < alert_target_view_storage_ids_.size(); ++i) {
 901     int view_storage_id = alert_target_view_storage_ids_[i];
 902     View* view = view_storage->RetrieveView(view_storage_id);
 903     if (!view || !view_->Contains(view))
 904       continue;
 905     alert_views.push_back(view);
 906   }
 907
 908   long count = alert_views.size();
 909   if (count == 0)
 910     return S_FALSE;
 911
 912   // Don't return more targets than max_targets - but note that the caller
 913   // is allowed to specify max_targets=0 to mean no limit.
 914   if (max_targets > 0 && count > max_targets)
 915     count = max_targets;
 916
 917   // Return the number of targets.
 918   *n_targets = count;
 919
 920   // Allocate COM memory for the result array and populate it.
 921   *targets = static_cast<IUnknown**>(
 922       CoTaskMemAlloc(count * sizeof(IUnknown*)));
 923   for (long i = 0; i < count; ++i) {
 924     (*targets)[i] = alert_views[i]->GetNativeViewAccessible();
 925     (*targets)[i]->AddRef();
 926   }
 927   return S_OK;
 928 }
 929
 930 STDMETHODIMP NativeViewAccessibilityWin::get_attributes(BSTR* attributes) {
 931   if (!view_)
 932     return E_FAIL;
 933
 934   if (!attributes)
 935     return E_INVALIDARG;
 936
 937   base::string16 attributes_str;
 938
 939   // Text fields need to report the attribute "text-model:a1" to instruct
 940   // screen readers to use IAccessible2 APIs to handle text editing in this
 941   // object (as opposed to treating it like a native Windows text box).
 942   // The text-model:a1 attribute is documented here:
 943   // http://www.linuxfoundation.org/collaborate/workgroups/accessibility/ia2/ia2_implementation_guide
 944   ui::AXViewState state;
 945   view_->GetAccessibleState(&state);
 946   if (state.role == ui::AX_ROLE_TEXT_FIELD) {
 947     attributes_str = L"text-model:a1;";
 948   }
 949
 950   *attributes = SysAllocString(attributes_str.c_str());
 951   DCHECK(*attributes);
 952   return S_OK;
 953 }
 954
 955 //
 956 // IAccessibleText
 957 //
 958
 959 STDMETHODIMP NativeViewAccessibilityWin::get_nCharacters(LONG* n_characters) {
 960   if (!view_)
 961     return E_FAIL;
 962
 963   if (!n_characters)
 964     return E_INVALIDARG;
 965
 966   base::string16 text = TextForIAccessibleText();
 967   *n_characters = static_cast<LONG>(text.size());
 968   return S_OK;
 969 }
 970
 971 STDMETHODIMP NativeViewAccessibilityWin::get_caretOffset(LONG* offset) {
 972   if (!view_)
 973     return E_FAIL;
 974
 975   if (!offset)
 976     return E_INVALIDARG;
 977
 978   ui::AXViewState state;
 979   view_->GetAccessibleState(&state);
 980   *offset = static_cast<LONG>(state.selection_end);
 981   return S_OK;
 982 }
 983
 984 STDMETHODIMP NativeViewAccessibilityWin::get_nSelections(LONG* n_selections) {
 985   if (!view_)
 986     return E_FAIL;
 987
 988   if (!n_selections)
 989     return E_INVALIDARG;
 990
 991   ui::AXViewState state;
 992   view_->GetAccessibleState(&state);
 993   if (state.selection_start != state.selection_end)
 994     *n_selections = 1;
 995   else
 996     *n_selections = 0;
 997   return S_OK;
 998 }
 999
1000 STDMETHODIMP NativeViewAccessibilityWin::get_selection(LONG selection_index,
1001                                                       LONG* start_offset,
1002                                                       LONG* end_offset) {
1003   if (!view_)
1004     return E_FAIL;
1005
1006   if (!start_offset || !end_offset || selection_index != 0)
1007     return E_INVALIDARG;
1008
1009   ui::AXViewState state;
1010   view_->GetAccessibleState(&state);
1011   *start_offset = static_cast<LONG>(state.selection_start);
1012   *end_offset = static_cast<LONG>(state.selection_end);
1013   return S_OK;
1014 }
1015
1016 STDMETHODIMP NativeViewAccessibilityWin::get_text(LONG start_offset,
1017                                                   LONG end_offset,
1018                                                   BSTR* text) {
1019   if (!view_)
1020     return E_FAIL;
1021
1022   ui::AXViewState state;
1023   view_->GetAccessibleState(&state);
1024   base::string16 text_str = TextForIAccessibleText();
1025   LONG len = static_cast<LONG>(text_str.size());
1026
1027   if (start_offset == IA2_TEXT_OFFSET_LENGTH) {
1028     start_offset = len;
1029   } else if (start_offset == IA2_TEXT_OFFSET_CARET) {
1030     start_offset = static_cast<LONG>(state.selection_end);
1031   }
1032   if (end_offset == IA2_TEXT_OFFSET_LENGTH) {
1033     end_offset = static_cast<LONG>(text_str.size());
1034   } else if (end_offset == IA2_TEXT_OFFSET_CARET) {
1035     end_offset = static_cast<LONG>(state.selection_end);
1036   }
1037
1038   // The spec allows the arguments to be reversed.
1039   if (start_offset > end_offset) {
1040     LONG tmp = start_offset;
1041     start_offset = end_offset;
1042     end_offset = tmp;
1043   }
1044
1045   // The spec does not allow the start or end offsets to be out or range;
1046   // we must return an error if so.
1047   if (start_offset < 0)
1048     return E_INVALIDARG;
1049   if (end_offset > len)
1050     return E_INVALIDARG;
1051
1052   base::string16 substr =
1053       text_str.substr(start_offset, end_offset - start_offset);
1054   if (substr.empty())
1055     return S_FALSE;
1056
1057   *text = SysAllocString(substr.c_str());
1058   DCHECK(*text);
1059   return S_OK;
1060 }
1061
1062 STDMETHODIMP NativeViewAccessibilityWin::get_textAtOffset(
1063     LONG offset,
1064     enum IA2TextBoundaryType boundary_type,
1065     LONG* start_offset, LONG* end_offset,
1066     BSTR* text) {
1067   if (!start_offset || !end_offset || !text)
1068     return E_INVALIDARG;
1069
1070   // The IAccessible2 spec says we don't have to implement the "sentence"
1071   // boundary type, we can just let the screenreader handle it.
1072   if (boundary_type == IA2_TEXT_BOUNDARY_SENTENCE) {
1073     *start_offset = 0;
1074     *end_offset = 0;
1075     *text = NULL;
1076     return S_FALSE;
1077   }
1078
1079   const base::string16& text_str = TextForIAccessibleText();
1080
1081   *start_offset = FindBoundary(
1082       text_str, boundary_type, offset, ui::BACKWARDS_DIRECTION);
1083   *end_offset = FindBoundary(
1084       text_str, boundary_type, offset, ui::FORWARDS_DIRECTION);
1085   return get_text(*start_offset, *end_offset, text);
1086 }
1087
1088 STDMETHODIMP NativeViewAccessibilityWin::get_textBeforeOffset(
1089     LONG offset,
1090     enum IA2TextBoundaryType boundary_type,
1091     LONG* start_offset, LONG* end_offset,
1092     BSTR* text) {
1093   if (!start_offset || !end_offset || !text)
1094     return E_INVALIDARG;
1095
1096   // The IAccessible2 spec says we don't have to implement the "sentence"
1097   // boundary type, we can just let the screenreader handle it.
1098   if (boundary_type == IA2_TEXT_BOUNDARY_SENTENCE) {
1099     *start_offset = 0;
1100     *end_offset = 0;
1101     *text = NULL;
1102     return S_FALSE;
1103   }
1104
1105   const base::string16& text_str = TextForIAccessibleText();
1106
1107   *start_offset = FindBoundary(
1108       text_str, boundary_type, offset, ui::BACKWARDS_DIRECTION);
1109   *end_offset = offset;
1110   return get_text(*start_offset, *end_offset, text);
1111 }
1112
1113 STDMETHODIMP NativeViewAccessibilityWin::get_textAfterOffset(
1114     LONG offset,
1115     enum IA2TextBoundaryType boundary_type,
1116     LONG* start_offset, LONG* end_offset,
1117     BSTR* text) {
1118   if (!start_offset || !end_offset || !text)
1119     return E_INVALIDARG;
1120
1121   // The IAccessible2 spec says we don't have to implement the "sentence"
1122   // boundary type, we can just let the screenreader handle it.
1123   if (boundary_type == IA2_TEXT_BOUNDARY_SENTENCE) {
1124     *start_offset = 0;
1125     *end_offset = 0;
1126     *text = NULL;
1127     return S_FALSE;
1128   }
1129
1130   const base::string16& text_str = TextForIAccessibleText();
1131
1132   *start_offset = offset;
1133   *end_offset = FindBoundary(
1134       text_str, boundary_type, offset, ui::FORWARDS_DIRECTION);
1135   return get_text(*start_offset, *end_offset, text);
1136 }
1137
1138 STDMETHODIMP NativeViewAccessibilityWin::get_offsetAtPoint(
1139     LONG x, LONG y, enum IA2CoordinateType coord_type, LONG* offset) {
1140   if (!view_)
1141     return E_FAIL;
1142
1143   if (!offset)
1144     return E_INVALIDARG;
1145
1146   // We don't support this method, but we have to return something
1147   // rather than E_NOTIMPL or screen readers will complain.
1148   *offset = 0;
1149   return S_OK;
1150 }
1151
1152 //
1153 // IServiceProvider methods.
1154 //
1155
1156 STDMETHODIMP NativeViewAccessibilityWin::QueryService(
1157     REFGUID guidService, REFIID riid, void** object) {
1158   if (!view_)
1159     return E_FAIL;
1160
1161   if (riid == IID_IAccessible2 || riid == IID_IAccessible2_2)
1162     AccessibleWebViewRegistry::GetInstance()->EnableIAccessible2Support();
1163
1164   if (guidService == IID_IAccessible ||
1165       guidService == IID_IAccessible2 ||
1166       guidService == IID_IAccessible2_2 ||
1167       guidService == IID_IAccessibleText)  {
1168     return QueryInterface(riid, object);
1169   }
1170
1171   // We only support the IAccessibleEx interface on Windows 8 and above. This
1172   // is needed for the On screen Keyboard to show up in metro mode, when the
1173   // user taps an editable region in the window.
1174   // All methods in the IAccessibleEx interface are unimplemented.
1175   if (riid == IID_IAccessibleEx &&
1176       base::win::GetVersion() >= base::win::VERSION_WIN8) {
1177     return QueryInterface(riid, object);
1178   }
1179
1180   *object = NULL;
1181   return E_FAIL;
1182 }
1183
1184 STDMETHODIMP NativeViewAccessibilityWin::GetPatternProvider(
1185     PATTERNID id, IUnknown** provider) {
1186   DVLOG(1) << "In Function: "
1187            << __FUNCTION__
1188            << " for pattern id: "
1189            << id;
1190   if (id == UIA_ValuePatternId || id == UIA_TextPatternId) {
1191     ui::AXViewState state;
1192     view_->GetAccessibleState(&state);
1193     long role = MSAARole(state.role);
1194
1195     if (role == ROLE_SYSTEM_TEXT) {
1196       DVLOG(1) << "Returning UIA text provider";
1197       base::win::UIATextProvider::CreateTextProvider(
1198           state.value, true, provider);
1199       return S_OK;
1200     }
1201   }
1202   return E_NOTIMPL;
1203 }
1204
1205 STDMETHODIMP NativeViewAccessibilityWin::GetPropertyValue(PROPERTYID id,
1206                                                           VARIANT* ret) {
1207   DVLOG(1) << "In Function: "
1208            << __FUNCTION__
1209            << " for property id: "
1210            << id;
1211   if (id == UIA_ControlTypePropertyId) {
1212     ui::AXViewState state;
1213     view_->GetAccessibleState(&state);
1214     long role = MSAARole(state.role);
1215     if (role == ROLE_SYSTEM_TEXT) {
1216       V_VT(ret) = VT_I4;
1217       ret->lVal = UIA_EditControlTypeId;
1218       DVLOG(1) << "Returning Edit control type";
1219     } else {
1220       DVLOG(1) << "Returning empty control type";
1221       V_VT(ret) = VT_EMPTY;
1222     }
1223   } else {
1224     V_VT(ret) = VT_EMPTY;
1225   }
1226   return S_OK;
1227 }
1228
1229 //
1230 // Static methods.
1231 //
1232
1233 void NativeViewAccessibility::RegisterWebView(View* web_view) {
1234   AccessibleWebViewRegistry::GetInstance()->RegisterWebView(web_view);
1235 }
1236
1237 void NativeViewAccessibility::UnregisterWebView(View* web_view) {
1238   AccessibleWebViewRegistry::GetInstance()->UnregisterWebView(web_view);
1239 }
1240
1241 int32 NativeViewAccessibilityWin::MSAAEvent(ui::AXEvent event) {
1242   switch (event) {
1243     case ui::AX_EVENT_ALERT:
1244       return EVENT_SYSTEM_ALERT;
1245     case ui::AX_EVENT_FOCUS:
1246       return EVENT_OBJECT_FOCUS;
1247     case ui::AX_EVENT_MENU_START:
1248       return EVENT_SYSTEM_MENUSTART;
1249     case ui::AX_EVENT_MENU_END:
1250       return EVENT_SYSTEM_MENUEND;
1251     case ui::AX_EVENT_MENU_POPUP_START:
1252       return EVENT_SYSTEM_MENUPOPUPSTART;
1253     case ui::AX_EVENT_MENU_POPUP_END:
1254       return EVENT_SYSTEM_MENUPOPUPEND;
1255     case ui::AX_EVENT_SELECTION:
1256       return EVENT_OBJECT_SELECTION;
1257     case ui::AX_EVENT_SELECTION_ADD:
1258       return EVENT_OBJECT_SELECTIONADD;
1259     case ui::AX_EVENT_SELECTION_REMOVE:
1260       return EVENT_OBJECT_SELECTIONREMOVE;
1261     case ui::AX_EVENT_TEXT_CHANGED:
1262       return EVENT_OBJECT_NAMECHANGE;
1263     case ui::AX_EVENT_TEXT_SELECTION_CHANGED:
1264       return IA2_EVENT_TEXT_CARET_MOVED;
1265     case ui::AX_EVENT_VALUE_CHANGED:
1266       return EVENT_OBJECT_VALUECHANGE;
1267     default:
1268       // Not supported or invalid event.
1269       NOTREACHED();
1270       return -1;
1271   }
1272 }
1273
1274 int32 NativeViewAccessibilityWin::MSAARole(ui::AXRole role) {
1275   switch (role) {
1276     case ui::AX_ROLE_ALERT:
1277       return ROLE_SYSTEM_ALERT;
1278     case ui::AX_ROLE_APPLICATION:
1279       return ROLE_SYSTEM_APPLICATION;
1280     case ui::AX_ROLE_BUTTON_DROP_DOWN:
1281       return ROLE_SYSTEM_BUTTONDROPDOWN;
1282     case ui::AX_ROLE_POP_UP_BUTTON:
1283       return ROLE_SYSTEM_BUTTONMENU;
1284     case ui::AX_ROLE_CHECK_BOX:
1285       return ROLE_SYSTEM_CHECKBUTTON;
1286     case ui::AX_ROLE_COMBO_BOX:
1287       return ROLE_SYSTEM_COMBOBOX;
1288     case ui::AX_ROLE_DIALOG:
1289       return ROLE_SYSTEM_DIALOG;
1290     case ui::AX_ROLE_GROUP:
1291       return ROLE_SYSTEM_GROUPING;
1292     case ui::AX_ROLE_IMAGE:
1293       return ROLE_SYSTEM_GRAPHIC;
1294     case ui::AX_ROLE_LINK:
1295       return ROLE_SYSTEM_LINK;
1296     case ui::AX_ROLE_LOCATION_BAR:
1297       return ROLE_SYSTEM_GROUPING;
1298     case ui::AX_ROLE_MENU_BAR:
1299       return ROLE_SYSTEM_MENUBAR;
1300     case ui::AX_ROLE_MENU_ITEM:
1301       return ROLE_SYSTEM_MENUITEM;
1302     case ui::AX_ROLE_MENU_LIST_POPUP:
1303       return ROLE_SYSTEM_MENUPOPUP;
1304     case ui::AX_ROLE_TREE:
1305       return ROLE_SYSTEM_OUTLINE;
1306     case ui::AX_ROLE_TREE_ITEM:
1307       return ROLE_SYSTEM_OUTLINEITEM;
1308     case ui::AX_ROLE_TAB:
1309       return ROLE_SYSTEM_PAGETAB;
1310     case ui::AX_ROLE_TAB_LIST:
1311       return ROLE_SYSTEM_PAGETABLIST;
1312     case ui::AX_ROLE_PANE:
1313       return ROLE_SYSTEM_PANE;
1314     case ui::AX_ROLE_PROGRESS_INDICATOR:
1315       return ROLE_SYSTEM_PROGRESSBAR;
1316     case ui::AX_ROLE_BUTTON:
1317       return ROLE_SYSTEM_PUSHBUTTON;
1318     case ui::AX_ROLE_RADIO_BUTTON:
1319       return ROLE_SYSTEM_RADIOBUTTON;
1320     case ui::AX_ROLE_SCROLL_BAR:
1321       return ROLE_SYSTEM_SCROLLBAR;
1322     case ui::AX_ROLE_SPLITTER:
1323       return ROLE_SYSTEM_SEPARATOR;
1324     case ui::AX_ROLE_SLIDER:
1325       return ROLE_SYSTEM_SLIDER;
1326     case ui::AX_ROLE_STATIC_TEXT:
1327       return ROLE_SYSTEM_STATICTEXT;
1328     case ui::AX_ROLE_TEXT_FIELD:
1329       return ROLE_SYSTEM_TEXT;
1330     case ui::AX_ROLE_TITLE_BAR:
1331       return ROLE_SYSTEM_TITLEBAR;
1332     case ui::AX_ROLE_TOOLBAR:
1333       return ROLE_SYSTEM_TOOLBAR;
1334     case ui::AX_ROLE_WINDOW:
1335       return ROLE_SYSTEM_WINDOW;
1336     case ui::AX_ROLE_CLIENT:
1337     default:
1338       // This is the default role for MSAA.
1339       return ROLE_SYSTEM_CLIENT;
1340   }
1341 }
1342
1343 int32 NativeViewAccessibilityWin::MSAAState(const ui::AXViewState& state) {
1344   // This maps MSAA states for get_accState(). See also the IAccessible2
1345   // interface get_states().
1346
1347   int32 msaa_state = 0;
1348   if (state.HasStateFlag(ui::AX_STATE_CHECKED))
1349     msaa_state |= STATE_SYSTEM_CHECKED;
1350   if (state.HasStateFlag(ui::AX_STATE_COLLAPSED))
1351     msaa_state |= STATE_SYSTEM_COLLAPSED;
1352   if (state.HasStateFlag(ui::AX_STATE_DEFAULT))
1353     msaa_state |= STATE_SYSTEM_DEFAULT;
1354   if (state.HasStateFlag(ui::AX_STATE_EXPANDED))
1355     msaa_state |= STATE_SYSTEM_EXPANDED;
1356   if (state.HasStateFlag(ui::AX_STATE_HASPOPUP))
1357     msaa_state |= STATE_SYSTEM_HASPOPUP;
1358   if (state.HasStateFlag(ui::AX_STATE_HOVERED))
1359     msaa_state |= STATE_SYSTEM_HOTTRACKED;
1360   if (state.HasStateFlag(ui::AX_STATE_INVISIBLE))
1361     msaa_state |= STATE_SYSTEM_INVISIBLE;
1362   if (state.HasStateFlag(ui::AX_STATE_LINKED))
1363     msaa_state |= STATE_SYSTEM_LINKED;
1364   if (state.HasStateFlag(ui::AX_STATE_OFFSCREEN))
1365     msaa_state |= STATE_SYSTEM_OFFSCREEN;
1366   if (state.HasStateFlag(ui::AX_STATE_PRESSED))
1367     msaa_state |= STATE_SYSTEM_PRESSED;
1368   if (state.HasStateFlag(ui::AX_STATE_PROTECTED))
1369     msaa_state |= STATE_SYSTEM_PROTECTED;
1370   if (state.HasStateFlag(ui::AX_STATE_READ_ONLY))
1371     msaa_state |= STATE_SYSTEM_READONLY;
1372   if (state.HasStateFlag(ui::AX_STATE_SELECTABLE))
1373     msaa_state |= STATE_SYSTEM_SELECTABLE;
1374   if (state.HasStateFlag(ui::AX_STATE_SELECTED))
1375     msaa_state |= STATE_SYSTEM_SELECTED;
1376   if (state.HasStateFlag(ui::AX_STATE_FOCUSED))
1377     msaa_state |= STATE_SYSTEM_FOCUSED;
1378   if (state.HasStateFlag(ui::AX_STATE_DISABLED))
1379     msaa_state |= STATE_SYSTEM_UNAVAILABLE;
1380   return msaa_state;
1381 }
1382
1383 //
1384 // Private methods.
1385 //
1386
1387 bool NativeViewAccessibilityWin::IsNavDirNext(int nav_dir) const {
1388   return (nav_dir == NAVDIR_RIGHT ||
1389           nav_dir == NAVDIR_DOWN ||
1390           nav_dir == NAVDIR_NEXT);
1391 }
1392
1393 bool NativeViewAccessibilityWin::IsValidNav(
1394     int nav_dir, int start_id, int lower_bound, int upper_bound) const {
1395   if (IsNavDirNext(nav_dir)) {
1396     if ((start_id + 1) > upper_bound) {
1397       return false;
1398     }
1399   } else {
1400     if ((start_id - 1) <= lower_bound) {
1401       return false;
1402     }
1403   }
1404   return true;
1405 }
1406
1407 bool NativeViewAccessibilityWin::IsValidId(const VARIANT& child) const {
1408   // View accessibility returns an IAccessible for each view so we only support
1409   // the CHILDID_SELF id.
1410   return (VT_I4 == child.vt) && (CHILDID_SELF == child.lVal);
1411 }
1412
1413 void NativeViewAccessibilityWin::SetState(
1414     VARIANT* msaa_state, View* view) {
1415   // Ensure the output param is initialized to zero.
1416   msaa_state->lVal = 0;
1417
1418   // Default state; all views can have accessibility focus.
1419   msaa_state->lVal |= STATE_SYSTEM_FOCUSABLE;
1420
1421   if (!view)
1422     return;
1423
1424   if (!view->enabled())
1425     msaa_state->lVal |= STATE_SYSTEM_UNAVAILABLE;
1426   if (!view->visible())
1427     msaa_state->lVal |= STATE_SYSTEM_INVISIBLE;
1428   if (!strcmp(view->GetClassName(), CustomButton::kViewClassName)) {
1429     CustomButton* button = static_cast<CustomButton*>(view);
1430     if (button->IsHotTracked())
1431       msaa_state->lVal |= STATE_SYSTEM_HOTTRACKED;
1432   }
1433   if (view->HasFocus())
1434     msaa_state->lVal |= STATE_SYSTEM_FOCUSED;
1435
1436   // Add on any view-specific states.
1437   ui::AXViewState view_state;
1438   view->GetAccessibleState(&view_state);
1439   msaa_state->lVal |= MSAAState(view_state);
1440 }
1441
1442 base::string16 NativeViewAccessibilityWin::TextForIAccessibleText() {
1443   ui::AXViewState state;
1444   view_->GetAccessibleState(&state);
1445   if (state.role == ui::AX_ROLE_TEXT_FIELD)
1446     return state.value;
1447   else
1448     return state.name;
1449 }
1450
1451 void NativeViewAccessibilityWin::HandleSpecialTextOffset(
1452     const base::string16& text, LONG* offset) {
1453   if (*offset == IA2_TEXT_OFFSET_LENGTH) {
1454     *offset = static_cast<LONG>(text.size());
1455   } else if (*offset == IA2_TEXT_OFFSET_CARET) {
1456     get_caretOffset(offset);
1457   }
1458 }
1459
1460 ui::TextBoundaryType NativeViewAccessibilityWin::IA2TextBoundaryToTextBoundary(
1461     IA2TextBoundaryType ia2_boundary) {
1462   switch(ia2_boundary) {
1463     case IA2_TEXT_BOUNDARY_CHAR: return ui::CHAR_BOUNDARY;
1464     case IA2_TEXT_BOUNDARY_WORD: return ui::WORD_BOUNDARY;
1465     case IA2_TEXT_BOUNDARY_LINE: return ui::LINE_BOUNDARY;
1466     case IA2_TEXT_BOUNDARY_SENTENCE: return ui::SENTENCE_BOUNDARY;
1467     case IA2_TEXT_BOUNDARY_PARAGRAPH: return ui::PARAGRAPH_BOUNDARY;
1468     case IA2_TEXT_BOUNDARY_ALL: return ui::ALL_BOUNDARY;
1469     default:
1470       NOTREACHED();
1471       return ui::CHAR_BOUNDARY;
1472   }
1473 }
1474
1475 LONG NativeViewAccessibilityWin::FindBoundary(
1476     const base::string16& text,
1477     IA2TextBoundaryType ia2_boundary,
1478     LONG start_offset,
1479     ui::TextBoundaryDirection direction) {
1480   HandleSpecialTextOffset(text, &start_offset);
1481   ui::TextBoundaryType boundary = IA2TextBoundaryToTextBoundary(ia2_boundary);
1482   std::vector<int32> line_breaks;
1483   return ui::FindAccessibleTextBoundary(
1484       text, line_breaks, boundary, start_offset, direction);
1485 }
1486
1487 void NativeViewAccessibilityWin::PopulateChildWidgetVector(
1488     std::vector<Widget*>* result_child_widgets) {
1489   const Widget* widget = view()->GetWidget();
1490   if (!widget)
1491     return;
1492
1493   std::set<Widget*> child_widgets;
1494   Widget::GetAllOwnedWidgets(widget->GetNativeView(), &child_widgets);
1495   for (std::set<Widget*>::const_iterator iter = child_widgets.begin();
1496            iter != child_widgets.end(); ++iter) {
1497     Widget* child_widget = *iter;
1498     DCHECK_NE(widget, child_widget);
1499
1500     if (!child_widget->IsVisible())
1501       continue;
1502
1503     if (widget->GetNativeWindowProperty(kWidgetNativeViewHostKey))
1504       continue;
1505
1506     result_child_widgets->push_back(child_widget);
1507   }
1508 }
1509
1510 void NativeViewAccessibilityWin::AddAlertTarget() {
1511   ViewStorage* view_storage = ViewStorage::GetInstance();
1512   for (size_t i = 0; i < alert_target_view_storage_ids_.size(); ++i) {
1513     int view_storage_id = alert_target_view_storage_ids_[i];
1514     View* view = view_storage->RetrieveView(view_storage_id);
1515     if (view == view_)
1516       return;
1517   }
1518   int view_storage_id = view_storage->CreateStorageID();
1519   view_storage->StoreView(view_storage_id, view_);
1520   alert_target_view_storage_ids_.push_back(view_storage_id);
1521 }
1522
1523 void NativeViewAccessibilityWin::RemoveAlertTarget() {
1524   ViewStorage* view_storage = ViewStorage::GetInstance();
1525   size_t i = 0;
1526   while (i < alert_target_view_storage_ids_.size()) {
1527     int view_storage_id = alert_target_view_storage_ids_[i];
1528     View* view = view_storage->RetrieveView(view_storage_id);
1529     if (view == NULL || view == view_) {
1530       alert_target_view_storage_ids_.erase(
1531           alert_target_view_storage_ids_.begin() + i);
1532     } else {
1533       ++i;
1534     }
1535   }
1536 }
1537
1538 }  // namespace views