1 // Copyright (c) 2011 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 #ifndef CHROME_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_WIN_H_ 6 #define CHROME_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_WIN_H_ 7 #pragma once 8 9 #include <atlbase.h> 10 #include <atlcom.h> 11 #include <oleacc.h> 12 13 #include <vector> 14 15 #include "chrome/browser/accessibility/browser_accessibility.h" 16 #include "ia2_api_all.h" // Generated 17 #include "ISimpleDOMDocument.h" // Generated 18 #include "ISimpleDOMNode.h" // Generated 19 #include "ISimpleDOMText.h" // Generated 20 #include "webkit/glue/webaccessibility.h" 21 22 class BrowserAccessibilityManagerWin; 23 24 using webkit_glue::WebAccessibility; 25 26 //////////////////////////////////////////////////////////////////////////////// 27 // 28 // BrowserAccessibilityWin 29 // 30 // Class implementing the windows accessible interface for the Browser-Renderer 31 // communication of accessibility information, providing accessibility 32 // to be used by screen readers and other assistive technology (AT). 33 // 34 //////////////////////////////////////////////////////////////////////////////// 35 class BrowserAccessibilityWin 36 : public BrowserAccessibility, 37 public CComObjectRootEx<CComMultiThreadModel>, 38 public IDispatchImpl<IAccessible2, &IID_IAccessible2, 39 &LIBID_IAccessible2Lib>, 40 public IAccessibleImage, 41 public IAccessibleText, 42 public IServiceProvider, 43 public ISimpleDOMDocument, 44 public ISimpleDOMNode, 45 public ISimpleDOMText { 46 public: 47 BEGIN_COM_MAP(BrowserAccessibilityWin) 48 COM_INTERFACE_ENTRY2(IDispatch, IAccessible2) 49 COM_INTERFACE_ENTRY2(IAccessible, IAccessible2) 50 COM_INTERFACE_ENTRY(IAccessible2) 51 COM_INTERFACE_ENTRY(IAccessibleImage) 52 COM_INTERFACE_ENTRY(IAccessibleText) 53 COM_INTERFACE_ENTRY(IServiceProvider) 54 COM_INTERFACE_ENTRY(ISimpleDOMDocument) 55 COM_INTERFACE_ENTRY(ISimpleDOMNode) 56 COM_INTERFACE_ENTRY(ISimpleDOMText) 57 END_COM_MAP() 58 59 BrowserAccessibilityWin(); 60 61 virtual ~BrowserAccessibilityWin(); 62 63 // 64 // BrowserAccessibility methods. 65 // 66 virtual void Initialize(); 67 virtual void NativeAddReference(); 68 virtual void NativeReleaseReference(); 69 70 // 71 // IAccessible methods. 72 // 73 74 // Performs the default action on a given object. 75 STDMETHODIMP accDoDefaultAction(VARIANT var_id); 76 77 // Retrieves the child element or child object at a given point on the screen. 78 STDMETHODIMP accHitTest(LONG x_left, LONG y_top, VARIANT* child); 79 80 // Retrieves the specified object's current screen location. 81 STDMETHODIMP accLocation(LONG* x_left, 82 LONG* y_top, 83 LONG* width, 84 LONG* height, 85 VARIANT var_id); 86 87 // Traverses to another UI element and retrieves the object. 88 STDMETHODIMP accNavigate(LONG nav_dir, VARIANT start, VARIANT* end); 89 90 // Retrieves an IDispatch interface pointer for the specified child. 91 STDMETHODIMP get_accChild(VARIANT var_child, IDispatch** disp_child); 92 93 // Retrieves the number of accessible children. 94 STDMETHODIMP get_accChildCount(LONG* child_count); 95 96 // Retrieves a string that describes the object's default action. 97 STDMETHODIMP get_accDefaultAction(VARIANT var_id, BSTR* default_action); 98 99 // Retrieves the object's description. 100 STDMETHODIMP get_accDescription(VARIANT var_id, BSTR* desc); 101 102 // Retrieves the object that has the keyboard focus. 103 STDMETHODIMP get_accFocus(VARIANT* focus_child); 104 105 // Retrieves the help information associated with the object. 106 STDMETHODIMP get_accHelp(VARIANT var_id, BSTR* help); 107 108 // Retrieves the specified object's shortcut. 109 STDMETHODIMP get_accKeyboardShortcut(VARIANT var_id, BSTR* access_key); 110 111 // Retrieves the name of the specified object. 112 STDMETHODIMP get_accName(VARIANT var_id, BSTR* name); 113 114 // Retrieves the IDispatch interface of the object's parent. 115 STDMETHODIMP get_accParent(IDispatch** disp_parent); 116 117 // Retrieves information describing the role of the specified object. 118 STDMETHODIMP get_accRole(VARIANT var_id, VARIANT* role); 119 120 // Retrieves the current state of the specified object. 121 STDMETHODIMP get_accState(VARIANT var_id, VARIANT* state); 122 123 // Returns the value associated with the object. 124 STDMETHODIMP get_accValue(VARIANT var_id, BSTR* value); 125 126 // Make an object take focus or extend the selection. 127 STDMETHODIMP accSelect(LONG flags_sel, VARIANT var_id); 128 129 STDMETHODIMP get_accHelpTopic(BSTR* help_file, 130 VARIANT var_id, 131 LONG* topic_id); 132 133 STDMETHODIMP get_accSelection(VARIANT* selected); 134 135 // Deprecated methods, not implemented. 136 STDMETHODIMP put_accName(VARIANT var_id, BSTR put_name) { 137 return E_NOTIMPL; 138 } 139 STDMETHODIMP put_accValue(VARIANT var_id, BSTR put_val) { 140 return E_NOTIMPL; 141 } 142 143 // 144 // IAccessible2 methods. 145 // 146 147 // Returns role from a longer list of possible roles. 148 STDMETHODIMP role(LONG* role); 149 150 // Returns the state bitmask from a larger set of possible states. 151 STDMETHODIMP get_states(AccessibleStates* states); 152 153 // Returns the attributes specific to this IAccessible2 object, 154 // such as a cell's formula. 155 STDMETHODIMP get_attributes(BSTR* attributes); 156 157 // Get the unique ID of this object so that the client knows if it's 158 // been encountered previously. 159 STDMETHODIMP get_uniqueID(LONG* unique_id); 160 161 // Get the window handle of the enclosing window. 162 STDMETHODIMP get_windowHandle(HWND* window_handle); 163 164 // Get this object's index in its parent object. 165 STDMETHODIMP get_indexInParent(LONG* index_in_parent); 166 167 // IAccessible2 methods not implemented. 168 STDMETHODIMP get_extendedRole(BSTR* extended_role) { 169 return E_NOTIMPL; 170 } 171 STDMETHODIMP get_nRelations(LONG* n_relations) { 172 return E_NOTIMPL; 173 } 174 STDMETHODIMP get_relation(LONG relation_index, 175 IAccessibleRelation** relation) { 176 return E_NOTIMPL; 177 } 178 STDMETHODIMP get_relations(LONG max_relations, 179 IAccessibleRelation** relations, 180 LONG* n_relations) { 181 return E_NOTIMPL; 182 } 183 STDMETHODIMP scrollTo(enum IA2ScrollType scroll_type) { 184 return E_NOTIMPL; 185 } 186 STDMETHODIMP scrollToPoint(enum IA2CoordinateType coordinate_type, 187 LONG x, 188 LONG y) { 189 return E_NOTIMPL; 190 } 191 STDMETHODIMP get_groupPosition(LONG* group_level, 192 LONG* similar_items_in_group, 193 LONG* position_in_group) { 194 return E_NOTIMPL; 195 } 196 STDMETHODIMP get_localizedExtendedRole(BSTR* localized_extended_role) { 197 return E_NOTIMPL; 198 } 199 STDMETHODIMP get_nExtendedStates(LONG* n_extended_states) { 200 return E_NOTIMPL; 201 } 202 STDMETHODIMP get_extendedStates(LONG max_extended_states, 203 BSTR** extended_states, 204 LONG* n_extended_states) { 205 return E_NOTIMPL; 206 } 207 STDMETHODIMP get_localizedExtendedStates(LONG max_localized_extended_states, 208 BSTR** localized_extended_states, 209 LONG* n_localized_extended_states) { 210 return E_NOTIMPL; 211 } 212 STDMETHODIMP get_locale(IA2Locale* locale) { 213 return E_NOTIMPL; 214 } 215 216 // 217 // IAccessibleImage methods. 218 // 219 220 STDMETHODIMP get_description(BSTR* description); 221 222 STDMETHODIMP get_imagePosition(enum IA2CoordinateType coordinate_type, 223 LONG* x, LONG* y); 224 225 STDMETHODIMP get_imageSize(LONG* height, LONG* width); 226 227 // 228 // IAccessibleText methods. 229 // 230 231 STDMETHODIMP get_nCharacters(LONG* n_characters); 232 233 STDMETHODIMP get_caretOffset(LONG* offset); 234 235 STDMETHODIMP get_nSelections(LONG* n_selections); 236 237 STDMETHODIMP get_selection(LONG selection_index, 238 LONG* start_offset, 239 LONG* end_offset); 240 241 STDMETHODIMP get_text(LONG start_offset, LONG end_offset, BSTR* text); 242 243 STDMETHODIMP get_textAtOffset(LONG offset, 244 enum IA2TextBoundaryType boundary_type, 245 LONG* start_offset, LONG* end_offset, 246 BSTR* text); 247 248 STDMETHODIMP get_textBeforeOffset(LONG offset, 249 enum IA2TextBoundaryType boundary_type, 250 LONG* start_offset, LONG* end_offset, 251 BSTR* text); 252 253 STDMETHODIMP get_textAfterOffset(LONG offset, 254 enum IA2TextBoundaryType boundary_type, 255 LONG* start_offset, LONG* end_offset, 256 BSTR* text); 257 258 // IAccessibleText methods not implemented. 259 STDMETHODIMP addSelection(LONG start_offset, LONG end_offset) { 260 return E_NOTIMPL; 261 } 262 STDMETHODIMP get_attributes(LONG offset, LONG* start_offset, LONG* end_offset, 263 BSTR* text_attributes) { 264 return E_NOTIMPL; 265 } 266 STDMETHODIMP get_characterExtents(LONG offset, 267 enum IA2CoordinateType coord_type, 268 LONG* x, LONG* y, 269 LONG* width, LONG* height) { 270 return E_NOTIMPL; 271 } 272 STDMETHODIMP get_offsetAtPoint(LONG x, LONG y, 273 enum IA2CoordinateType coord_type, 274 LONG* offset) { 275 return E_NOTIMPL; 276 } 277 STDMETHODIMP removeSelection(LONG selection_index) { 278 return E_NOTIMPL; 279 } 280 STDMETHODIMP setCaretOffset(LONG offset) { 281 return E_NOTIMPL; 282 } 283 STDMETHODIMP setSelection(LONG selection_index, 284 LONG start_offset, 285 LONG end_offset) { 286 return E_NOTIMPL; 287 } 288 STDMETHODIMP scrollSubstringTo(LONG start_index, 289 LONG end_index, 290 enum IA2ScrollType scroll_type) { 291 return E_NOTIMPL; 292 } 293 STDMETHODIMP scrollSubstringToPoint(LONG start_index, LONG end_index, 294 enum IA2CoordinateType coordinate_type, 295 LONG x, LONG y) { 296 return E_NOTIMPL; 297 } 298 STDMETHODIMP get_newText(IA2TextSegment* new_text) { 299 return E_NOTIMPL; 300 } 301 STDMETHODIMP get_oldText(IA2TextSegment* old_text) { 302 return E_NOTIMPL; 303 } 304 305 // 306 // ISimpleDOMDocument methods. 307 // 308 309 STDMETHODIMP get_URL(BSTR* url); 310 311 STDMETHODIMP get_title(BSTR* title); 312 313 STDMETHODIMP get_mimeType(BSTR* mime_type); 314 315 STDMETHODIMP get_docType(BSTR* doc_type); 316 317 STDMETHODIMP get_nameSpaceURIForID( 318 short name_space_id, BSTR *name_space_uri) { 319 return E_NOTIMPL; 320 } 321 STDMETHODIMP put_alternateViewMediaTypes( 322 BSTR *comma_separated_media_types) { 323 return E_NOTIMPL; 324 } 325 326 // 327 // ISimpleDOMNode methods. 328 // 329 330 STDMETHODIMP get_nodeInfo( 331 BSTR* node_name, 332 short* name_space_id, 333 BSTR* node_value, 334 unsigned int* num_children, 335 unsigned int* unique_id, 336 unsigned short* node_type); 337 338 STDMETHODIMP get_attributes( 339 unsigned short max_attribs, 340 BSTR* attrib_names, 341 short* name_space_id, 342 BSTR* attrib_values, 343 unsigned short* num_attribs); 344 345 STDMETHODIMP get_attributesForNames( 346 unsigned short num_attribs, 347 BSTR* attrib_names, 348 short* name_space_id, 349 BSTR* attrib_values); 350 351 STDMETHODIMP get_computedStyle( 352 unsigned short max_style_properties, 353 boolean use_alternate_view, 354 BSTR *style_properties, 355 BSTR *style_values, 356 unsigned short *num_style_properties); 357 358 STDMETHODIMP get_computedStyleForProperties( 359 unsigned short num_style_properties, 360 boolean use_alternate_view, 361 BSTR* style_properties, 362 BSTR* style_values); 363 364 STDMETHODIMP scrollTo(boolean placeTopLeft); 365 366 STDMETHODIMP get_parentNode(ISimpleDOMNode** node); 367 368 STDMETHODIMP get_firstChild(ISimpleDOMNode** node); 369 370 STDMETHODIMP get_lastChild(ISimpleDOMNode** node); 371 372 STDMETHODIMP get_previousSibling(ISimpleDOMNode** node); 373 374 STDMETHODIMP get_nextSibling(ISimpleDOMNode** node); 375 376 STDMETHODIMP get_childAt( 377 unsigned int child_index, 378 ISimpleDOMNode** node); 379 380 STDMETHODIMP get_innerHTML(BSTR* innerHTML) { 381 return E_NOTIMPL; 382 } 383 384 STDMETHODIMP get_localInterface(void** local_interface) { 385 return E_NOTIMPL; 386 } 387 388 STDMETHODIMP get_language(BSTR* language) { 389 return E_NOTIMPL; 390 } 391 392 // 393 // ISimpleDOMText methods. 394 // 395 396 STDMETHODIMP get_domText(BSTR* dom_text); 397 398 STDMETHODIMP get_clippedSubstringBounds( 399 unsigned int start_index, 400 unsigned int end_index, 401 int* x, 402 int* y, 403 int* width, 404 int* height) { 405 return E_NOTIMPL; 406 } 407 408 STDMETHODIMP get_unclippedSubstringBounds( 409 unsigned int start_index, 410 unsigned int end_index, 411 int* x, 412 int* y, 413 int* width, 414 int* height) { 415 return E_NOTIMPL; 416 } 417 418 STDMETHODIMP scrollToSubstring( 419 unsigned int start_index, 420 unsigned int end_index) { 421 return E_NOTIMPL; 422 } 423 424 STDMETHODIMP get_fontFamily(BSTR *font_family) { 425 return E_NOTIMPL; 426 } 427 428 // 429 // IServiceProvider methods. 430 // 431 432 STDMETHODIMP QueryService(REFGUID guidService, REFIID riid, void** object); 433 434 // 435 // CComObjectRootEx methods. 436 // 437 438 HRESULT WINAPI InternalQueryInterface(void* this_ptr, 439 const _ATL_INTMAP_ENTRY* entries, 440 REFIID iid, 441 void** object); 442 443 private: 444 // Add one to the reference count and return the same object. Always 445 // use this method when returning a BrowserAccessibilityWin object as 446 // an output parameter to a COM interface, never use it otherwise. 447 BrowserAccessibilityWin* NewReference(); 448 449 // Many MSAA methods take a var_id parameter indicating that the operation 450 // should be performed on a particular child ID, rather than this object. 451 // This method tries to figure out the target object from |var_id| and 452 // returns a pointer to the target object if it exists, otherwise NULL. 453 // Does not return a new reference. 454 BrowserAccessibilityWin* GetTargetFromChildID(const VARIANT& var_id); 455 456 // Initialize the role and state metadata from the role enum and state 457 // bitmasks defined in webkit/glue/webaccessibility.h. 458 void InitRoleAndState(); 459 460 // Retrieve the string value of an attribute from the attribute map and 461 // if found and nonempty, allocate a new BSTR (with SysAllocString) 462 // and return S_OK. If not found or empty, return S_FALSE. 463 HRESULT GetAttributeAsBstr( 464 WebAccessibility::Attribute attribute, BSTR* value_bstr); 465 466 // Escape a string like it would be escaped for a URL or HTML form. 467 string16 Escape(const string16& str); 468 469 // Get the text of this node for the purposes of IAccessibleText - it may 470 // be the name, it may be the value, etc. depending on the role. 471 const string16& TextForIAccessibleText(); 472 473 // Search forwards (direction == 1) or backwards (direction == -1) from 474 // the given offset until the given IAccessible2 boundary (like word, 475 // sentence) is found, and return its offset. 476 LONG FindBoundary(const string16& text, 477 IA2TextBoundaryType boundary, 478 LONG start_offset, 479 LONG direction); 480 481 // IAccessible role and state. 482 int32 ia_role_; 483 int32 ia_state_; 484 485 // IAccessible2 role and state. 486 int32 ia2_role_; 487 int32 ia2_state_; 488 489 // Give BrowserAccessibility::Create access to our constructor. 490 friend class BrowserAccessibility; 491 492 DISALLOW_COPY_AND_ASSIGN(BrowserAccessibilityWin); 493 }; 494 495 #endif // CHROME_BROWSER_ACCESSIBILITY_BROWSER_ACCESSIBILITY_WIN_H_ 496
