content/browser/accessibility/browser_accessibility_android.cc

   1 // Copyright 2013 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 "content/browser/accessibility/browser_accessibility_android.h"
   6
   7 #include "base/strings/utf_string_conversions.h"
   8 #include "content/browser/accessibility/browser_accessibility_manager_android.h"
   9 #include "content/common/accessibility_messages.h"
  10
  11 namespace {
  12
  13 // These are enums from android.text.InputType in Java:
  14 enum {
  15   ANDROID_TEXT_INPUTTYPE_TYPE_NULL = 0,
  16   ANDROID_TEXT_INPUTTYPE_TYPE_DATETIME = 0x4,
  17   ANDROID_TEXT_INPUTTYPE_TYPE_DATETIME_DATE = 0x14,
  18   ANDROID_TEXT_INPUTTYPE_TYPE_DATETIME_TIME = 0x24,
  19   ANDROID_TEXT_INPUTTYPE_TYPE_NUMBER = 0x2,
  20   ANDROID_TEXT_INPUTTYPE_TYPE_PHONE = 0x3,
  21   ANDROID_TEXT_INPUTTYPE_TYPE_TEXT = 0x1,
  22   ANDROID_TEXT_INPUTTYPE_TYPE_TEXT_URI = 0x11,
  23   ANDROID_TEXT_INPUTTYPE_TYPE_TEXT_WEB_EDIT_TEXT = 0xa1,
  24   ANDROID_TEXT_INPUTTYPE_TYPE_TEXT_WEB_EMAIL = 0xd1,
  25   ANDROID_TEXT_INPUTTYPE_TYPE_TEXT_WEB_PASSWORD = 0xe1
  26 };
  27
  28 // These are enums from android.view.View in Java:
  29 enum {
  30   ANDROID_VIEW_VIEW_ACCESSIBILITY_LIVE_REGION_NONE = 0,
  31   ANDROID_VIEW_VIEW_ACCESSIBILITY_LIVE_REGION_POLITE = 1,
  32   ANDROID_VIEW_VIEW_ACCESSIBILITY_LIVE_REGION_ASSERTIVE = 2
  33 };
  34
  35 // These are enums from
  36 // android.view.accessibility.AccessibilityNodeInfo.RangeInfo in Java:
  37 enum {
  38   ANDROID_VIEW_ACCESSIBILITY_RANGE_TYPE_FLOAT = 1
  39 };
  40
  41 }  // namespace
  42
  43 namespace content {
  44
  45 // static
  46 BrowserAccessibility* BrowserAccessibility::Create() {
  47   return new BrowserAccessibilityAndroid();
  48 }
  49
  50 BrowserAccessibilityAndroid::BrowserAccessibilityAndroid() {
  51   first_time_ = true;
  52 }
  53
  54 bool BrowserAccessibilityAndroid::IsNative() const {
  55   return true;
  56 }
  57
  58 bool BrowserAccessibilityAndroid::PlatformIsLeaf() const {
  59   if (InternalChildCount() == 0)
  60     return true;
  61
  62   // Iframes are always allowed to contain children.
  63   if (IsIframe() ||
  64       GetRole() == ui::AX_ROLE_ROOT_WEB_AREA ||
  65       GetRole() == ui::AX_ROLE_WEB_AREA) {
  66     return false;
  67   }
  68
  69   // If it has a focusable child, we definitely can't leave out children.
  70   if (HasFocusableChild())
  71     return false;
  72
  73   // Headings with text can drop their children.
  74   base::string16 name = GetText();
  75   if (GetRole() == ui::AX_ROLE_HEADING && !name.empty())
  76     return true;
  77
  78   // Focusable nodes with text can drop their children.
  79   if (HasState(ui::AX_STATE_FOCUSABLE) && !name.empty())
  80     return true;
  81
  82   // Nodes with only static text as children can drop their children.
  83   if (HasOnlyStaticTextChildren())
  84     return true;
  85
  86   return BrowserAccessibility::PlatformIsLeaf();
  87 }
  88
  89 bool BrowserAccessibilityAndroid::IsCheckable() const {
  90   bool checkable = false;
  91   bool is_aria_pressed_defined;
  92   bool is_mixed;
  93   GetAriaTristate("aria-pressed", &is_aria_pressed_defined, &is_mixed);
  94   if (GetRole() == ui::AX_ROLE_CHECK_BOX ||
  95       GetRole() == ui::AX_ROLE_RADIO_BUTTON ||
  96       is_aria_pressed_defined) {
  97     checkable = true;
  98   }
  99   if (HasState(ui::AX_STATE_CHECKED))
 100     checkable = true;
 101   return checkable;
 102 }
 103
 104 bool BrowserAccessibilityAndroid::IsChecked() const {
 105   return HasState(ui::AX_STATE_CHECKED);
 106 }
 107
 108 bool BrowserAccessibilityAndroid::IsClickable() const {
 109   return (PlatformIsLeaf() && !GetText().empty());
 110 }
 111
 112 bool BrowserAccessibilityAndroid::IsCollection() const {
 113   return (GetRole() == ui::AX_ROLE_GRID ||
 114           GetRole() == ui::AX_ROLE_LIST ||
 115           GetRole() == ui::AX_ROLE_LIST_BOX ||
 116           GetRole() == ui::AX_ROLE_TABLE ||
 117           GetRole() == ui::AX_ROLE_TREE);
 118 }
 119
 120 bool BrowserAccessibilityAndroid::IsCollectionItem() const {
 121   return (GetRole() == ui::AX_ROLE_CELL ||
 122           GetRole() == ui::AX_ROLE_COLUMN_HEADER ||
 123           GetRole() == ui::AX_ROLE_DESCRIPTION_LIST_TERM ||
 124           GetRole() == ui::AX_ROLE_LIST_BOX_OPTION ||
 125           GetRole() == ui::AX_ROLE_LIST_ITEM ||
 126           GetRole() == ui::AX_ROLE_ROW_HEADER ||
 127           GetRole() == ui::AX_ROLE_TREE_ITEM);
 128 }
 129
 130 bool BrowserAccessibilityAndroid::IsContentInvalid() const {
 131   std::string invalid;
 132   return GetHtmlAttribute("aria-invalid", &invalid);
 133 }
 134
 135 bool BrowserAccessibilityAndroid::IsDismissable() const {
 136   return false;  // No concept of "dismissable" on the web currently.
 137 }
 138
 139 bool BrowserAccessibilityAndroid::IsEnabled() const {
 140   return HasState(ui::AX_STATE_ENABLED);
 141 }
 142
 143 bool BrowserAccessibilityAndroid::IsFocusable() const {
 144   bool focusable = HasState(ui::AX_STATE_FOCUSABLE);
 145   if (IsIframe() ||
 146       GetRole() == ui::AX_ROLE_WEB_AREA) {
 147     focusable = false;
 148   }
 149   return focusable;
 150 }
 151
 152 bool BrowserAccessibilityAndroid::IsFocused() const {
 153   return manager()->GetFocus(manager()->GetRoot()) == this;
 154 }
 155
 156 bool BrowserAccessibilityAndroid::IsHeading() const {
 157   return (GetRole() == ui::AX_ROLE_COLUMN_HEADER ||
 158           GetRole() == ui::AX_ROLE_HEADING ||
 159           GetRole() == ui::AX_ROLE_ROW_HEADER);
 160 }
 161
 162 bool BrowserAccessibilityAndroid::IsHierarchical() const {
 163   return (GetRole() == ui::AX_ROLE_LIST ||
 164           GetRole() == ui::AX_ROLE_TREE);
 165 }
 166
 167 bool BrowserAccessibilityAndroid::IsLink() const {
 168   return GetRole() == ui::AX_ROLE_LINK ||
 169          GetRole() == ui::AX_ROLE_IMAGE_MAP_LINK;
 170 }
 171
 172 bool BrowserAccessibilityAndroid::IsMultiLine() const {
 173   return GetRole() == ui::AX_ROLE_TEXT_AREA;
 174 }
 175
 176 bool BrowserAccessibilityAndroid::IsPassword() const {
 177   return HasState(ui::AX_STATE_PROTECTED);
 178 }
 179
 180 bool BrowserAccessibilityAndroid::IsRangeType() const {
 181   return (GetRole() == ui::AX_ROLE_PROGRESS_INDICATOR ||
 182           GetRole() == ui::AX_ROLE_SCROLL_BAR ||
 183           GetRole() == ui::AX_ROLE_SLIDER);
 184 }
 185
 186 bool BrowserAccessibilityAndroid::IsScrollable() const {
 187   int dummy;
 188   return GetIntAttribute(ui::AX_ATTR_SCROLL_X_MAX, &dummy);
 189 }
 190
 191 bool BrowserAccessibilityAndroid::IsSelected() const {
 192   return HasState(ui::AX_STATE_SELECTED);
 193 }
 194
 195 bool BrowserAccessibilityAndroid::IsVisibleToUser() const {
 196   return !HasState(ui::AX_STATE_INVISIBLE);
 197 }
 198
 199 bool BrowserAccessibilityAndroid::CanOpenPopup() const {
 200   return HasState(ui::AX_STATE_HASPOPUP);
 201 }
 202
 203 const char* BrowserAccessibilityAndroid::GetClassName() const {
 204   const char* class_name = NULL;
 205
 206   switch(GetRole()) {
 207     case ui::AX_ROLE_EDITABLE_TEXT:
 208     case ui::AX_ROLE_SPIN_BUTTON:
 209     case ui::AX_ROLE_TEXT_AREA:
 210     case ui::AX_ROLE_TEXT_FIELD:
 211       class_name = "android.widget.EditText";
 212       break;
 213     case ui::AX_ROLE_SLIDER:
 214       class_name = "android.widget.SeekBar";
 215       break;
 216     case ui::AX_ROLE_COMBO_BOX:
 217       class_name = "android.widget.Spinner";
 218       break;
 219     case ui::AX_ROLE_BUTTON:
 220     case ui::AX_ROLE_MENU_BUTTON:
 221     case ui::AX_ROLE_POP_UP_BUTTON:
 222       class_name = "android.widget.Button";
 223       break;
 224     case ui::AX_ROLE_CHECK_BOX:
 225       class_name = "android.widget.CheckBox";
 226       break;
 227     case ui::AX_ROLE_RADIO_BUTTON:
 228       class_name = "android.widget.RadioButton";
 229       break;
 230     case ui::AX_ROLE_TOGGLE_BUTTON:
 231       class_name = "android.widget.ToggleButton";
 232       break;
 233     case ui::AX_ROLE_CANVAS:
 234     case ui::AX_ROLE_IMAGE:
 235       class_name = "android.widget.Image";
 236       break;
 237     case ui::AX_ROLE_PROGRESS_INDICATOR:
 238       class_name = "android.widget.ProgressBar";
 239       break;
 240     case ui::AX_ROLE_TAB_LIST:
 241       class_name = "android.widget.TabWidget";
 242       break;
 243     case ui::AX_ROLE_GRID:
 244     case ui::AX_ROLE_TABLE:
 245       class_name = "android.widget.GridView";
 246       break;
 247     case ui::AX_ROLE_LIST:
 248     case ui::AX_ROLE_LIST_BOX:
 249       class_name = "android.widget.ListView";
 250       break;
 251     case ui::AX_ROLE_DIALOG:
 252       class_name = "android.app.Dialog";
 253       break;
 254     case ui::AX_ROLE_ROOT_WEB_AREA:
 255       class_name = "android.webkit.WebView";
 256       break;
 257     default:
 258       class_name = "android.view.View";
 259       break;
 260   }
 261
 262   return class_name;
 263 }
 264
 265 base::string16 BrowserAccessibilityAndroid::GetText() const {
 266   if (IsIframe() ||
 267       GetRole() == ui::AX_ROLE_WEB_AREA) {
 268     return base::string16();
 269   }
 270
 271   // See comment in browser_accessibility_win.cc for details.
 272   // The difference here is that we can only expose one accessible
 273   // name on Android, not 2 or 3 like on Windows or Mac.
 274   //
 275   // The basic rule is: prefer description (aria-labelledby or aria-label),
 276   // then help (title), then name (inner text), then value (control value).
 277   // However, if title_elem_id is set, that means there's a label element
 278   // supplying the name and then name takes precedence over help.
 279   // TODO(dmazzoni): clean this up by providing more granular labels in
 280   // Blink, making the platform-specific mapping to accessible text simpler.
 281   base::string16 description = GetString16Attribute(ui::AX_ATTR_DESCRIPTION);
 282   base::string16 help = GetString16Attribute(ui::AX_ATTR_HELP);
 283   int title_elem_id = GetIntAttribute(
 284       ui::AX_ATTR_TITLE_UI_ELEMENT);
 285   base::string16 text;
 286   if (!description.empty())
 287     text = description;
 288   else if (title_elem_id && !name().empty())
 289     text = base::UTF8ToUTF16(name());
 290   else if (!help.empty())
 291     text = help;
 292   else if (!name().empty())
 293     text = base::UTF8ToUTF16(name());
 294   else if (!value().empty())
 295     text = base::UTF8ToUTF16(value());
 296
 297   // This is called from PlatformIsLeaf, so don't call PlatformChildCount
 298   // from within this!
 299   if (text.empty() && HasOnlyStaticTextChildren()) {
 300     for (uint32 i = 0; i < InternalChildCount(); i++) {
 301       BrowserAccessibility* child = InternalGetChild(i);
 302       text += static_cast<BrowserAccessibilityAndroid*>(child)->GetText();
 303     }
 304   }
 305
 306   switch(GetRole()) {
 307     case ui::AX_ROLE_HEADING:
 308       // Only append "heading" if this node already has text.
 309       if (!text.empty())
 310         text += base::ASCIIToUTF16(" Heading");
 311       break;
 312   }
 313
 314   if (text.empty() && IsLink()) {
 315     base::string16 url = GetString16Attribute(ui::AX_ATTR_URL);
 316     // Given a url like http://foo.com/bar/baz.png, just return the
 317     // base name, e.g., "baz".
 318     int trailing_slashes = 0;
 319     while (url.size() - trailing_slashes > 0 &&
 320            url[url.size() - trailing_slashes - 1] == '/') {
 321       trailing_slashes++;
 322     }
 323     if (trailing_slashes)
 324       url = url.substr(0, url.size() - trailing_slashes);
 325     size_t slash_index = url.rfind('/');
 326     if (slash_index != std::string::npos)
 327       url = url.substr(slash_index + 1);
 328     size_t dot_index = url.rfind('.');
 329     if (dot_index != std::string::npos)
 330       url = url.substr(0, dot_index);
 331     text = url;
 332   }
 333
 334   return text;
 335 }
 336
 337 int BrowserAccessibilityAndroid::GetItemIndex() const {
 338   int index = 0;
 339   switch(GetRole()) {
 340     case ui::AX_ROLE_LIST_ITEM:
 341     case ui::AX_ROLE_LIST_BOX_OPTION:
 342     case ui::AX_ROLE_TREE_ITEM:
 343       index = GetIndexInParent();
 344       break;
 345     case ui::AX_ROLE_SLIDER:
 346     case ui::AX_ROLE_PROGRESS_INDICATOR: {
 347       float value_for_range;
 348       if (GetFloatAttribute(
 349               ui::AX_ATTR_VALUE_FOR_RANGE, &value_for_range)) {
 350         index = static_cast<int>(value_for_range);
 351       }
 352       break;
 353     }
 354   }
 355   return index;
 356 }
 357
 358 int BrowserAccessibilityAndroid::GetItemCount() const {
 359   int count = 0;
 360   switch(GetRole()) {
 361     case ui::AX_ROLE_LIST:
 362     case ui::AX_ROLE_LIST_BOX:
 363       count = PlatformChildCount();
 364       break;
 365     case ui::AX_ROLE_SLIDER:
 366     case ui::AX_ROLE_PROGRESS_INDICATOR: {
 367       float max_value_for_range;
 368       if (GetFloatAttribute(ui::AX_ATTR_MAX_VALUE_FOR_RANGE,
 369                             &max_value_for_range)) {
 370         count = static_cast<int>(max_value_for_range);
 371       }
 372       break;
 373     }
 374   }
 375   return count;
 376 }
 377
 378 int BrowserAccessibilityAndroid::GetScrollX() const {
 379   int value = 0;
 380   GetIntAttribute(ui::AX_ATTR_SCROLL_X, &value);
 381   return value;
 382 }
 383
 384 int BrowserAccessibilityAndroid::GetScrollY() const {
 385   int value = 0;
 386   GetIntAttribute(ui::AX_ATTR_SCROLL_Y, &value);
 387   return value;
 388 }
 389
 390 int BrowserAccessibilityAndroid::GetMaxScrollX() const {
 391   int value = 0;
 392   GetIntAttribute(ui::AX_ATTR_SCROLL_X_MAX, &value);
 393   return value;
 394 }
 395
 396 int BrowserAccessibilityAndroid::GetMaxScrollY() const {
 397   int value = 0;
 398   GetIntAttribute(ui::AX_ATTR_SCROLL_Y_MAX, &value);
 399   return value;
 400 }
 401
 402 int BrowserAccessibilityAndroid::GetTextChangeFromIndex() const {
 403   size_t index = 0;
 404   while (index < old_value_.length() &&
 405          index < new_value_.length() &&
 406          old_value_[index] == new_value_[index]) {
 407     index++;
 408   }
 409   return index;
 410 }
 411
 412 int BrowserAccessibilityAndroid::GetTextChangeAddedCount() const {
 413   size_t old_len = old_value_.length();
 414   size_t new_len = new_value_.length();
 415   size_t left = 0;
 416   while (left < old_len &&
 417          left < new_len &&
 418          old_value_[left] == new_value_[left]) {
 419     left++;
 420   }
 421   size_t right = 0;
 422   while (right < old_len &&
 423          right < new_len &&
 424          old_value_[old_len - right - 1] == new_value_[new_len - right - 1]) {
 425     right++;
 426   }
 427   return (new_len - left - right);
 428 }
 429
 430 int BrowserAccessibilityAndroid::GetTextChangeRemovedCount() const {
 431   size_t old_len = old_value_.length();
 432   size_t new_len = new_value_.length();
 433   size_t left = 0;
 434   while (left < old_len &&
 435          left < new_len &&
 436          old_value_[left] == new_value_[left]) {
 437     left++;
 438   }
 439   size_t right = 0;
 440   while (right < old_len &&
 441          right < new_len &&
 442          old_value_[old_len - right - 1] == new_value_[new_len - right - 1]) {
 443     right++;
 444   }
 445   return (old_len - left - right);
 446 }
 447
 448 base::string16 BrowserAccessibilityAndroid::GetTextChangeBeforeText() const {
 449   return old_value_;
 450 }
 451
 452 int BrowserAccessibilityAndroid::GetSelectionStart() const {
 453   int sel_start = 0;
 454   GetIntAttribute(ui::AX_ATTR_TEXT_SEL_START, &sel_start);
 455   return sel_start;
 456 }
 457
 458 int BrowserAccessibilityAndroid::GetSelectionEnd() const {
 459   int sel_end = 0;
 460   GetIntAttribute(ui::AX_ATTR_TEXT_SEL_END, &sel_end);
 461   return sel_end;
 462 }
 463
 464 int BrowserAccessibilityAndroid::GetEditableTextLength() const {
 465   return value().length();
 466 }
 467
 468 int BrowserAccessibilityAndroid::AndroidInputType() const {
 469   std::string html_tag = GetStringAttribute(
 470       ui::AX_ATTR_HTML_TAG);
 471   if (html_tag != "input")
 472     return ANDROID_TEXT_INPUTTYPE_TYPE_NULL;
 473
 474   std::string type;
 475   if (!GetHtmlAttribute("type", &type))
 476     return ANDROID_TEXT_INPUTTYPE_TYPE_TEXT;
 477
 478   if (type == "" || type == "text" || type == "search")
 479     return ANDROID_TEXT_INPUTTYPE_TYPE_TEXT;
 480   else if (type == "date")
 481     return ANDROID_TEXT_INPUTTYPE_TYPE_DATETIME_DATE;
 482   else if (type == "datetime" || type == "datetime-local")
 483     return ANDROID_TEXT_INPUTTYPE_TYPE_DATETIME;
 484   else if (type == "email")
 485     return ANDROID_TEXT_INPUTTYPE_TYPE_TEXT_WEB_EMAIL;
 486   else if (type == "month")
 487     return ANDROID_TEXT_INPUTTYPE_TYPE_DATETIME_DATE;
 488   else if (type == "number")
 489     return ANDROID_TEXT_INPUTTYPE_TYPE_NUMBER;
 490   else if (type == "password")
 491     return ANDROID_TEXT_INPUTTYPE_TYPE_TEXT_WEB_PASSWORD;
 492   else if (type == "tel")
 493     return ANDROID_TEXT_INPUTTYPE_TYPE_PHONE;
 494   else if (type == "time")
 495     return ANDROID_TEXT_INPUTTYPE_TYPE_DATETIME_TIME;
 496   else if (type == "url")
 497     return ANDROID_TEXT_INPUTTYPE_TYPE_TEXT_URI;
 498   else if (type == "week")
 499     return ANDROID_TEXT_INPUTTYPE_TYPE_DATETIME;
 500
 501   return ANDROID_TEXT_INPUTTYPE_TYPE_NULL;
 502 }
 503
 504 int BrowserAccessibilityAndroid::AndroidLiveRegionType() const {
 505   std::string live = GetStringAttribute(
 506       ui::AX_ATTR_LIVE_STATUS);
 507   if (live == "polite")
 508     return ANDROID_VIEW_VIEW_ACCESSIBILITY_LIVE_REGION_POLITE;
 509   else if (live == "assertive")
 510     return ANDROID_VIEW_VIEW_ACCESSIBILITY_LIVE_REGION_ASSERTIVE;
 511   return ANDROID_VIEW_VIEW_ACCESSIBILITY_LIVE_REGION_NONE;
 512 }
 513
 514 int BrowserAccessibilityAndroid::AndroidRangeType() const {
 515   return ANDROID_VIEW_ACCESSIBILITY_RANGE_TYPE_FLOAT;
 516 }
 517
 518 int BrowserAccessibilityAndroid::RowCount() const {
 519   if (GetRole() == ui::AX_ROLE_GRID ||
 520       GetRole() == ui::AX_ROLE_TABLE) {
 521     return CountChildrenWithRole(ui::AX_ROLE_ROW);
 522   }
 523
 524   if (GetRole() == ui::AX_ROLE_LIST ||
 525       GetRole() == ui::AX_ROLE_LIST_BOX ||
 526       GetRole() == ui::AX_ROLE_TREE) {
 527     return PlatformChildCount();
 528   }
 529
 530   return 0;
 531 }
 532
 533 int BrowserAccessibilityAndroid::ColumnCount() const {
 534   if (GetRole() == ui::AX_ROLE_GRID ||
 535       GetRole() == ui::AX_ROLE_TABLE) {
 536     return CountChildrenWithRole(ui::AX_ROLE_COLUMN);
 537   }
 538   return 0;
 539 }
 540
 541 int BrowserAccessibilityAndroid::RowIndex() const {
 542   if (GetRole() == ui::AX_ROLE_LIST_ITEM ||
 543       GetRole() == ui::AX_ROLE_LIST_BOX_OPTION ||
 544       GetRole() == ui::AX_ROLE_TREE_ITEM) {
 545     return GetIndexInParent();
 546   }
 547
 548   return GetIntAttribute(ui::AX_ATTR_TABLE_CELL_ROW_INDEX);
 549 }
 550
 551 int BrowserAccessibilityAndroid::RowSpan() const {
 552   return GetIntAttribute(ui::AX_ATTR_TABLE_CELL_ROW_SPAN);
 553 }
 554
 555 int BrowserAccessibilityAndroid::ColumnIndex() const {
 556   return GetIntAttribute(ui::AX_ATTR_TABLE_CELL_COLUMN_INDEX);
 557 }
 558
 559 int BrowserAccessibilityAndroid::ColumnSpan() const {
 560   return GetIntAttribute(ui::AX_ATTR_TABLE_CELL_COLUMN_SPAN);
 561 }
 562
 563 float BrowserAccessibilityAndroid::RangeMin() const {
 564   return GetFloatAttribute(ui::AX_ATTR_MIN_VALUE_FOR_RANGE);
 565 }
 566
 567 float BrowserAccessibilityAndroid::RangeMax() const {
 568   return GetFloatAttribute(ui::AX_ATTR_MAX_VALUE_FOR_RANGE);
 569 }
 570
 571 float BrowserAccessibilityAndroid::RangeCurrentValue() const {
 572   return GetFloatAttribute(ui::AX_ATTR_VALUE_FOR_RANGE);
 573 }
 574
 575 bool BrowserAccessibilityAndroid::HasFocusableChild() const {
 576   // This is called from PlatformIsLeaf, so don't call PlatformChildCount
 577   // from within this!
 578   for (uint32 i = 0; i < InternalChildCount(); i++) {
 579     BrowserAccessibility* child = InternalGetChild(i);
 580     if (child->HasState(ui::AX_STATE_FOCUSABLE))
 581       return true;
 582     if (static_cast<BrowserAccessibilityAndroid*>(child)->HasFocusableChild())
 583       return true;
 584   }
 585   return false;
 586 }
 587
 588 bool BrowserAccessibilityAndroid::HasOnlyStaticTextChildren() const {
 589   // This is called from PlatformIsLeaf, so don't call PlatformChildCount
 590   // from within this!
 591   for (uint32 i = 0; i < InternalChildCount(); i++) {
 592     BrowserAccessibility* child = InternalGetChild(i);
 593     if (child->GetRole() != ui::AX_ROLE_STATIC_TEXT)
 594       return false;
 595   }
 596   return true;
 597 }
 598
 599 bool BrowserAccessibilityAndroid::IsIframe() const {
 600   base::string16 html_tag = GetString16Attribute(
 601       ui::AX_ATTR_HTML_TAG);
 602   return html_tag == base::ASCIIToUTF16("iframe");
 603 }
 604
 605 void BrowserAccessibilityAndroid::OnDataChanged() {
 606   BrowserAccessibility::OnDataChanged();
 607
 608   if (IsEditableText()) {
 609     if (base::UTF8ToUTF16(value()) != new_value_) {
 610       old_value_ = new_value_;
 611       new_value_ = base::UTF8ToUTF16(value());
 612     }
 613   }
 614
 615   if (GetRole() == ui::AX_ROLE_ALERT && first_time_)
 616     manager()->NotifyAccessibilityEvent(ui::AX_EVENT_ALERT, this);
 617
 618   base::string16 live;
 619   if (GetString16Attribute(
 620       ui::AX_ATTR_CONTAINER_LIVE_STATUS, &live)) {
 621     NotifyLiveRegionUpdate(live);
 622   }
 623
 624   first_time_ = false;
 625 }
 626
 627 void BrowserAccessibilityAndroid::NotifyLiveRegionUpdate(
 628     base::string16& aria_live) {
 629   if (!EqualsASCII(aria_live, aria_strings::kAriaLivePolite) &&
 630       !EqualsASCII(aria_live, aria_strings::kAriaLiveAssertive))
 631     return;
 632
 633   base::string16 text = GetText();
 634   if (cached_text_ != text) {
 635     if (!text.empty()) {
 636       manager()->NotifyAccessibilityEvent(ui::AX_EVENT_SHOW,
 637                                          this);
 638     }
 639     cached_text_ = text;
 640   }
 641 }
 642
 643 int BrowserAccessibilityAndroid::CountChildrenWithRole(ui::AXRole role) const {
 644   int count = 0;
 645   for (uint32 i = 0; i < PlatformChildCount(); i++) {
 646     if (PlatformGetChild(i)->GetRole() == role)
 647       count++;
 648   }
 649   return count;
 650 }
 651
 652 }  // namespace content