other-licenses/ia2/Accessible2.idl

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1 /*************************************************************************
2 *
3 * File Name (Accessible2.idl)
4 *
5 * IAccessible2 IDL Specification
6 *
7 * Copyright (c) 2007, 2013 Linux Foundation
8 * Copyright (c) 2006 IBM Corporation
9 * Copyright (c) 2000, 2006 Sun Microsystems, Inc.
10 * All rights reserved.
11 *
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 *
17 * 1. Redistributions of source code must retain the above copyright
18 * notice, this list of conditions and the following disclaimer.
19 *
20 * 2. Redistributions in binary form must reproduce the above
21 * copyright notice, this list of conditions and the following
22 * disclaimer in the documentation and/or other materials
23 * provided with the distribution.
24 *
25 * 3. Neither the name of the Linux Foundation nor the names of its
26 * contributors may be used to endorse or promote products
27 * derived from this software without specific prior written
28 * permission.
29 *
30 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
31 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
32 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
33 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
34 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
35 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
36 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
37 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
38 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
40 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
41 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
42 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
43 *
44 * This BSD License conforms to the Open Source Initiative "Simplified
45 * BSD License" as published at:
46 * http://www.opensource.org/licenses/bsd-license.php
47 *
48 * IAccessible2 is a trademark of the Linux Foundation. The IAccessible2
49 * mark may be used in accordance with the Linux Foundation Trademark
50 * Policy to indicate compliance with the IAccessible2 specification.
51 *
52 ************************************************************************/
53
54 /** @mainpage
55
56 @section _interfaces Interfaces
57 IAccessible2\n
58 IAccessible2_2\n
59 IAccessibleAction\n
60 IAccessibleApplication\n
61 IAccessibleComponent\n
62 IAccessibleDocument\n
63 IAccessibleEditableText\n
64 IAccessibleHypertext\n
65 IAccessibleHypertext2\n
66 IAccessibleHyperlink\n
67 IAccessibleImage\n
68 IAccessibleRelation\n
69 IAccessibleTable [Deprecated]\n
70 IAccessibleTable2\n
71 IAccessibleTableCell\n
72 IAccessibleText\n
73 IAccessibleText2\n
74 IAccessibleValue
75
76 @section _structs Structs
77 IA2Locale\n
78 IA2TableModelChange\n
79 IA2TextSegment
80
81 @section _enums Enums
82 ::IA2Actions values are predefined actions for use when implementing support for HTML5 media.\n
83 ::IA2CoordinateType values define the requested coordinate type (screen or parent window).\n
84 ::IA2EventID values identify events.\n
85 ::IA2Role values defines roles which are in addition to the existing MSAA roles.\n
86 ::IA2ScrollType values define where to place an object or substring on the screen.\n
87 ::IA2States values define states which are in addition to the existing MSAA states.\n
88 ::IA2TableModelChangeType values describe the kinds of changes made to a table (insert, delete, update).\n
89 ::IA2TextBoundaryType values define the requested text unit (character, word, sentence, line, paragraph).\n
90 ::IA2TextSpecialOffsets values define special offsets for use in the text interfaces.
91
92 @section _constants Constants
93 @ref grpRelations
94
95 @section _misc Miscellaneous
96 @ref _licensePage "BSD License"\n
97 @ref _generalInfo "General Information"\n
98
99 @page _licensePage BSD License
100 %IAccessible2 IDL Specification
101
102 Copyright (c) 2007, 2013 Linux Foundation\n
103 Copyright (c) 2006 IBM Corporation\n
104 Copyright (c) 2000, 2006 Sun Microsystems, Inc.\n
105 All rights reserved.
106
107 Redistribution and use in source and binary forms, with or without
108 modification, are permitted provided that the following conditions
109 are met:
110
111 1. Redistributions of source code must retain the above copyright
112 notice, this list of conditions and the following disclaimer.
113
114 2. Redistributions in binary form must reproduce the above
115 copyright notice, this list of conditions and the following
116 disclaimer in the documentation and/or other materials
117 provided with the distribution.
118
119 3. Neither the name of the Linux Foundation nor the names of its
120 contributors may be used to endorse or promote products
121 derived from this software without specific prior written
122 permission.
123
124 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
125 CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
126 INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
127 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
128 DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
129 CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
130 SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
131 NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
132 LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
133 HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
134 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
135 OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
136 EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
137
138 This BSD License conforms to the Open Source Initiative "Simplified
139 BSD License" as published at:
140 http://www.opensource.org/licenses/bsd-license.php
141
142 %IAccessible2 is a trademark of the Linux Foundation. The %IAccessible2
143 mark may be used in accordance with the
144 <a href="http://www.linuxfoundation.org/collaborate/workgroups/accessibility/trademark-policy">
145 Linux Foundation Trademark Policy</a> to indicate compliance with the %IAccessible2 specification.
146
147 @page _generalInfo General Information
148 The following information is applicable to two or more interfaces.
149
150 @ref _errors\n
151 @ref _memory\n
152 &nbsp;&nbsp;@ref _arrayConsideration\n
153 @ref _indexes\n
154 @ref _enums\n
155 @ref _specialOffsets\n
156 @ref _dicoveringInterfaces\n
157 @ref _changingInterfaces\n
158 @ref _applicationInfo\n
159 @ref _childIDs\n
160 @ref _variants\n
161 @ref _iaaction-iahyperlink\n
162 @ref _trademark
163
164 @section _errors Error Handling
165 HRESULT values are defined by the Microsoft&reg; Win32&reg; API. For more information, refer to
166 <a href="http://msdn.microsoft.com/en-us/library/windows/desktop/aa378137%28v=vs.85%29.aspx">
167 Interpreting HRESULT Values</a> in MSDN&reg;.
168
169 Note that the S_FALSE return value is considered a non-error value and the
170 SUCCEEDED macro will return TRUE. S_FALSE is used when there is no failure
171 but there was nothing valid to return, e.g. in IAccessible2::attributes when
172 there are no attributes. When S_FALSE is returned [out] pointer types should
173 be NULL and [out] longs should generally be 0, but sometimes -1 is used such
174 as IAccessible2::indexInParent, IAccessibleText::caretOffset, and
175 IAccessibleHypertext::hyperlinkIndex.
176
177 Note that for BSTR [out] variables common COM practice is that the server does
178 the SysAllocString and the client does the SysFreeString. Also note that when
179 NULL is returned there is no need for the client to call SysFreeString. Please
180 refer to the documentation for each method for more details regarding error handling.
181
182 @section _memory Memory Management
183 The following memory management issues should be considered:
184 @li Although [out] BSTR variables are declared by the client, their space is
185 allocated by the server. They need to be freed with SysFreeString by the
186 client at end of life; the same is true when BSTRs are used in structs or
187 arrays which are passed to the server.
188 @li If there is no valid [out] BSTR to return, the server should return S_FALSE and
189 assign NULL to the output, e.g. *theOutBSTR = NULL;.
190 @li COM interfaces need to be referenced with AddRef when used and dereferenced
191 with Release at end of life.
192 @li Single [out] longs, HWNDs, booleans, and structs are declared by the caller
193 and passed by reference. The marshaller does all the memory management.
194
195 The following articles may be helpful for understanding memory management issues:
196 @li An article by Don Box in a
197 <a href="http://www.microsoft.com/msj/1196/activex1196.aspx">Q & A section</a>
198 of the November 1996 edition of the Microsoft Systems Journal.
199 @li A posting to a CodeGuru forum,
200 <a href="http://www.codeguru.com/forum/showthread.php?t=364511">Windows SDK
201 String: What are the rules for BSTR allocation and deallocation?</a>
202
203 @subsection _arrayConsideration Special Consideration when using Arrays
204 There are several methods which return arrays. In the case of IAccessible2::relations
205 and IAccessibleRelation::targets the client must allocate and free the arrays.
206
207 For the remaining methods which return arrays, the server must allocate the array
208 and the client must free the array when no longer needed. These methods are
209 IAccessible2::extendedStates, IAccessible2::localizedExtendedStates,
210 IAccessible2_2::relationTargetsOfType, IAccessibleAction::keyBinding,
211 IAccessibleHypertext2::hyperlinks, IAccessibleTable::selectedChildren,
212 IAccessibleTable::selectedColumns, IAccessibleTable::selectedRows,
213 IAccessibleTable2::selectedCells, IAccessibleTable2::selectedColumns,
214 IAccessibleTable2::selectedRows, IAccessibleTableCell::columnHeaderCells,
215 and IAccessibleTableCell::rowHeaderCells.
216 For those methods, the server must allocate both the top level array and any storage
217 associated with it, e.g. for BSTRs. The server must allocate the arrays with
218 CoTaskMemAlloc and any BSTRs with SysAllocString. The client must use CoTaskMemFree
219 to free the array and any BSTRs must be freed with SysFreeString.
220
221 Also, the IDL for IAccessible2::extendedStates, IAccessible2::localizedExtendedStates,
222 IAccessibleAction::keyBinding, IAccessibleTable::selectedChildren,
223 IAccessibleTable::selectedColumns, and IAccessibleTable::selectedRows includes an
224 extraneous [in] parameter for the caller to specify the max size of the array.
225 This parameter will be ignored by the COM server.
226
227 @section _indexes Zero and One Based Indexes
228 Unless otherwise specified all offsets and indexes are 0 based.
229
230 @section _enums Enums
231 Note that enums start at 0.
232
233 @section _specialOffsets Special Offsets for use in the IAccessibleText and IAccessibleEditableText Methods
234 IAccessibleText and IAccessibleEditableText can use one or more of the following
235 special offset values. They are defined in the ::IA2TextSpecialOffsets enum.
236 @li Using ::IA2_TEXT_OFFSET_LENGTH (-1) as an offset in any of the IAccessibleText or
237 IAccessibleEditableText methods is the same as specifying the length of the string.
238 @li Using ::IA2_TEXT_OFFSET_CARET (-2) as an offset for IAccessibleText::textBeforeOffset,
239 IAccessibleText::textAtOffset, and IAccessibleText::textAfterOffset indicates that the
240 text related to the physical location of the caret should be used. This is needed for
241 applications that consider the character offset of the end of one line (as reached by
242 pressing the End key) the same as the offset of the first character on the next line.
243 Since the same offset is associated with two different lines a special means is needed
244 to fetch text from the line where the caret is physically located.
245
246 @section _dicoveringInterfaces Discovery of Interfaces
247 In general AT (Assistive Technology) should try IAccessible2 interfaces, followed by using
248 the MSAA (Microsoft&reg; Active Accessibility&reg;) interfaces. (In cases where the an application
249 is known to have custom interfaces which provide information not supplied by IAccessible2
250 or MSAA, then those custom interfaces can be used.) The AT can then, by default, support
251 unknown IAccessible2/MSAA applications, without the application developers having to request
252 AT vendors for support on an individual application by application basis.
253
254 When you have a reference to an IAccessible and require a reference to an IAccessible2 use
255 QueryService as follows:
256 @code
257 // pAcc is a reference to the accessible object's IAccessible interface.
258 IServiceProvider *pService = NULL;
259 hr = pAcc->QueryInterface(IID_IServiceProvider, (void **)&pService);
260 if(SUCCEEDED(hr)) {
261 IAccessible2 *pIA2 = NULL;
262 hr = pService->QueryService(IID_IAccessible, IID_IAccessible2, (void**)&pIA2);
263 if (SUCCEEDED(hr) && pIA2) {
264 // The control supports IAccessible2.
265 // pIA2 is the reference to the accessible object's IAccessible2 interface.
266 }
267 }
268 @endcode
269
270 @section _changingInterfaces Changing between Accessible Interfaces
271 Note that developers must always implement MSAA's IAccessible and, if needed, some
272 of the interfaces in the set of IAccessible2 interfaces. Although the IAccessible2
273 IDL is coded such that IAccessible2 is a subclass of MSAA's IAccessible, none of
274 MSAA's IAccessible methods are redefined by IAccessible2.
275
276 QueryService must be used to switch from a reference to an MSAA IAccessible interface
277 to another interface. This has been
278 <a href="http://www.atia.org/files/public/Introducing_IAccessibleEx.doc">
279 documented</a> and the pertinent facts have been extracted below:
280
281 @par
282 Why use QueryService instead of just using QueryInterface to get IAccessibleEx
283 directly? The reason is that since MSAA 2.0, clients don't talk to a server's
284 IAccessible interface directly; instead they talk to an intermediate MSAA-provided
285 wrapper that calls through to the original IAccessible. This wrapper provides services
286 such as implementing IDispatch, supplying information from MSAA 2.0's Dynamic Annotation
287 service, and scaling locations when running on Windows Vista with DPI scaling enabled.
288 QueryService is the supported way to expose additional interfaces from an existing
289 IAccessible and was originally used by MSHTML to expose IHTMLElement objects corresponding
290 to IAccessibles. QueryService is often more convenient for servers to implement than
291 QueryInterface because it does not have the same requirements for preserving object
292 identity or symmetry/transitivity as QueryInterface, so QueryService allows servers to
293 easily implement the interface on the same object or a separate object. The latter is
294 often hard to do with QueryInterface unless the original object supports aggregation.
295
296 Two related references in MSDN&reg; are:
297 @li <a href="http://msdn.microsoft.com/en-us/library/ms696078(VS.85).aspx">
298 "Using QueryService to expose a native object model interface for an IAccessible object"</a>
299 @li <a href="http://msdn.microsoft.com/en-us/library/ms528415.aspx#acc_obj">
300 "Accessing the Internet Explorer Object Associated with an Accessible Object"</a>
301
302 Based on this information from Microsoft, QueryService must be used to switch back and forth
303 between a reference to an MSAA IAccessible interface and any of the IAccessible2 interfaces.
304
305 Regarding switching between any of the IAccessible2 interfaces, applications implementing
306 IAccessible2 should implement the IAccessible2 interfaces on a single object since ATs
307 will be using QueryInterface to switch between the IAccessilbe2 interfaces. Implementing
308 the IAccessible2 interfaces on separate objects would require the use of QueryService.
309 There is one exception, IAccessibleApplication can be implemented on a separate object so
310 its common code doesn't have to be included in each accessible object. ATs should use
311 QueryService to access IAccessibleApplication.
312
313 @section _applicationInfo Access to Information about the Application
314 Servers implementing IAccessible2 should provide access to the IAccessibleApplication
315 interface via QueryService from any object so that ATs can easily determine specific
316 information about the application such as its name or version.
317
318 @section _childIDs Child IDs
319 The IAccessible2 interfaces do not support child IDs, i.e. simple child elements.
320 Full accessible objects must be created for each object that supports IAccessible2.
321 Therefore MSAA's get_accChild should never return a child ID (other than CHILDID_SELF)
322 for an object that implements any of the IAccessible2 interfaces.
323
324 Microsoft's UI Automation specification has the same limitation and this was resolved
325 in the UI Automation Express specification by adding IAccessibleEx::GetObjectForChild
326 and IAccessibleEx::GetIAccessiblePair. These methods allow mapping back and forth
327 between an IAccessibleEx and an {IAccessible, Child ID} pair. A future version of
328 IAccessible2 may include similar methods to map back and forth between an IAccessible2
329 and an {IAccessible, Child ID} pair.
330
331 @section _variants VARIANTs
332 Some methods return a VARIANT. Implementers need to make sure that the return type is
333 specified, i.e. VT_I4, VT_IDISPATCH, etc. The methods that return VARIANTs are
334 IAccessibleHyperlink::anchor, IAccessibleHyperlink::anchorTarget, IAccessibleValue::currentValue,
335 IAccessibleValue::maximumValue, IAccessibleValue::minimumValue.
336
337 @section _iaaction-iahyperlink IAccessibleHyperlink as subclass of IAccessibleAction
338 In this version of the IDL, IAccessibleHyperlink is a subclass of IAccessibleAction.
339 However, there is no practical need for that inheritance and in some cases, such as
340 an image map of smart tags, it doesn't make sense because such an image map doesn't
341 have actionable objects; it's the secondary smart tags that are actionable. As a
342 result, implementations should not rely on the inheritance as it may be removed in
343 a later version of the IDL.
344
345 @section _trademark Trademark Attribution
346 The names of actual companies and products mentioned herein may be the trademarks of
347 their respective owners. In particular, Active Accessibility, Microsoft, MSDN, and Win32
348 are trademarks of the Microsoft group of companies in the U.S.A. and/or other countries.
349
350 **/
351
352 import "objidl.idl";
353 import "oaidl.idl";
354 import "oleacc.idl";
355 import "AccessibleRelation.idl";
356 import "AccessibleStates.idl";
357 import "IA2CommonTypes.idl";
358
359 /** A structure defining the locale of an accessible object.
360
361 IAccessible2::locale returns this struct.
362 */
363 typedef struct IA2Locale {
364 BSTR language; ///< ISO 639-1 Alpha-2 two character language code
365 BSTR country; ///< ISO 3166-1 Alpha-2 two character country code
366 BSTR variant; ///< Application specific variant of the locale
367 } IA2Locale;
368
369 /** @brief This interface exposes the primary set of information about an
370 IAccessible2 enabled accessible object.
371
372 This interface must always be provided for objects that support some
373 portion of the collection of the %IAccessible2 interfaces.
374
375 Please refer to @ref _changingInterfaces "Changing between Accessible Interfaces"
376 for special considerations related to use of the MSAA IAccessible interface and
377 the set of %IAccessible2 interfaces.
378 */
379 [object, uuid(E89F726E-C4F4-4c19-BB19-B647D7FA8478)]
380 interface IAccessible2 : IAccessible
381 {
382
383 /** @brief Returns the number of accessible relations for this object.
384 @param [out] nRelations
385 @retval S_OK
386 */
387 [propget] HRESULT nRelations
388 (
389 [out, retval] long *nRelations
390 );
391
392 /** @brief Returns one accessible relation for this object.
393 @param [in] relationIndex
394 0 based
395 @param [out] relation
396 @retval S_OK
397 @retval E_INVALIDARG if bad [in] passed
398 */
399 [propget] HRESULT relation
400 (
401 [in] long relationIndex,
402 [out, retval] IAccessibleRelation **relation
403 );
404
405 /** @brief Returns multiple accessible relations for this object.
406 @param [in] maxRelations
407 maximum size of the array allocated by the client
408 @param [out] relations
409 The array of accessible relation objects. Note that this array is to be
410 allocated by the client and freed when no longer needed. Refer to @ref
411 _arrayConsideration "Special Consideration when using Arrays" for more details.
412 @param [out] nRelations
413 actual number of relations in the returned array (not more than maxRelations)
414 @retval S_OK
415 @retval S_FALSE if there are no relations, nRelations is set to 0
416 @note As a performant alternative, client code should consider using IAccessible2_2::relationTargetsOfType.
417 */
418 [propget] HRESULT relations
419 (
420 [in] long maxRelations,
421 [out, size_is(maxRelations), length_is(*nRelations)]
422 IAccessibleRelation **relations,
423 [out, retval] long *nRelations
424 );
425
426 /** @brief Returns the role of an %IAccessible2 object.
427 @param [out] role
428 The role of an %IAccessible2 object.
429 @retval S_OK
430 @note
431 @li For convenience MSAA roles are also passed through this method so the
432 AT doesn't have to also fetch roles through MSAA's get_accRole.
433 @li %IAccessible2 roles should not be passed through MSAA's get_accRole.
434 @li For compatibility with non IAccessible2 enabled ATs, IAccessible2
435 applications should also add support to get_accRole to return the closest
436 MSAA role or ROLE_SYSTEM_CLIENT (the MSAA defined default role) if there
437 is not a good match.
438 @li This method is missing a [propget] prefix in the IDL. The result is the
439 method is named role in generated C++ code instead of get_role.
440 */
441 HRESULT role
442 (
443 [out, retval] long *role
444 );
445
446 /** @brief Makes an object visible on the screen.
447 @param [in] scrollType
448 Defines where the object should be placed on the screen.
449 @retval S_OK
450 @retval E_INVALIDARG if bad [in] passed
451 */
452 HRESULT scrollTo
453 (
454 [in] enum IA2ScrollType scrollType
455 );
456
457 /** @brief Moves the top left of an object to a specified location.
458
459 @param [in] coordinateType
460 Specifies whether the coordinates are relative to the screen or the parent object.
461 @param [in] x
462 Defines the x coordinate.
463 @param [in] y
464 Defines the y coordinate.
465 @retval S_OK
466 @retval E_INVALIDARG if bad [in] passed
467 */
468 HRESULT scrollToPoint
469 (
470 [in] enum IA2CoordinateType coordinateType,
471 [in] long x,
472 [in] long y
473 );
474
475 /** @brief Returns grouping information.
476
477 Used for tree items, list items, tab panel labels, radio buttons, etc.
478 Also used for collections of non-text objects.
479
480 @param [out] groupLevel
481 1 based, 0 indicates that this value is not applicable
482 @param [out] similarItemsInGroup
483 1 based, 0 indicates that this value is not applicable
484 @param [out] positionInGroup
485 1 based, 0 indicates that this value is not applicable. This is an index
486 into the objects in the current group, not an index into all the objects
487 at the same group level.
488 @retval S_OK if at least one value is valid
489 @retval S_FALSE if no values are valid, [out] values are 0s
490 @note This method is meant to describe the nature of an object's containment
491 structure. It's exposed by trees, tree grids, nested lists, nested menus,
492 but not headings, which uses the level object attribute. It is also exposed
493 by radio buttons (with groupLevel == 0).
494 @note This is normally not implemented on a combo box to describe the nature
495 of its contents. Normally an AT will get that information from its child list
496 object. However, in some cases when non-edit combo boxes are not able to be structured
497 such that the list is a child of the combo box, this method is implemented on
498 the combo box itself. ATs can use this interface if a child list is not found.
499 */
500 [propget] HRESULT groupPosition
501 (
502 [out] long *groupLevel,
503 [out] long *similarItemsInGroup,
504 [out, retval] long *positionInGroup
505 );
506
507 /** @brief Returns the bit strip containing any IAccessible2 states.
508
509 The IAccessible2 states are in addition to the MSAA states and are defined in
510 the IA2States enum.
511
512 @param [out] states
513 @retval S_OK
514 */
515 [propget] HRESULT states
516 (
517 [out, retval] AccessibleStates *states
518 );
519
520 /** @brief Returns the extended role.
521
522 An extended role is a role which is dynamically generated by the application.
523 It is not predefined by the %IAccessible2 specification.
524
525 @param [out] extendedRole
526 @retval S_OK
527 @retval S_FALSE if there is nothing to return, [out] value is NULL
528 */
529 [propget] HRESULT extendedRole
530 (
531 [out, retval] BSTR *extendedRole
532 );
533
534 /** @brief Returns the localized extended role.
535 @param [out] localizedExtendedRole
536 @retval S_OK
537 @retval S_FALSE if there is nothing to return, [out] value is NULL
538 */
539 [propget] HRESULT localizedExtendedRole
540 (
541 [out, retval] BSTR *localizedExtendedRole
542 );
543
544 /** @brief Returns the number of extended states.
545 @param [out] nExtendedStates
546 @retval S_OK
547 */
548 [propget] HRESULT nExtendedStates
549 (
550 [out, retval] long *nExtendedStates
551 );
552
553 /** @brief Returns the extended states (array of strings).
554
555 An extended state is a state which is dynamically generated by the application.
556 It is not predefined by the %IAccessible2 specification.
557
558 @param [in] maxExtendedStates
559 This parameter is ignored. Refer to @ref _arrayConsideration
560 "Special Consideration when using Arrays" for more details.
561 @param [out] extendedStates
562 This array is allocated by the server. The client must free it with CoTaskMemFree.
563 @param [out] nExtendedStates
564 The number of extended states returned; the size of the returned array.
565 @retval S_OK
566 @retval S_FALSE if there are no states, [out] values are NULL and 0 respectively
567 */
568 [propget] HRESULT extendedStates
569 (
570 [in] long maxExtendedStates,
571 [out, size_is(,maxExtendedStates), length_is(,*nExtendedStates)] BSTR **extendedStates,
572 [out, retval] long *nExtendedStates
573 );
574
575 /** @brief Returns the localized extended states (array of strings).
576
577 @param [in] maxLocalizedExtendedStates
578 This parameter is ignored. Refer to @ref _arrayConsideration
579 "Special Consideration when using Arrays" for more details.
580 @param [out] localizedExtendedStates
581 This array is allocated by the server. The client must free it with CoTaskMemFree.
582 @param [out] nLocalizedExtendedStates
583 The number of localized extended states returned; the size of the returned array.
584 @retval S_OK
585 @retval S_FALSE if there are no states, [out] values are NULL and 0 respectively
586 */
587 [propget] HRESULT localizedExtendedStates
588 (
589 [in] long maxLocalizedExtendedStates,
590 [out, size_is(,maxLocalizedExtendedStates), length_is(,*nLocalizedExtendedStates)] BSTR **localizedExtendedStates,
591 [out, retval] long *nLocalizedExtendedStates
592 );
593
594 /** @brief Returns the unique ID.
595
596 The uniqueID is an identifier for this object, is unique within the
597 current window, and remains the same for the lifetime of the accessible
598 object.
599
600 The uniqueID is not related to:
601 - the MSAA objectID which is used by the server to disambiguate between
602 IAccessibles per HWND or
603 - the MSAA childID which is used to disambiguate between children being
604 managed by an IAccessible.
605
606 This value is provided so the AT can have access to a unique runtime persistent
607 identifier even when not handling an event for the object.
608
609 An example of when this value is useful is if the AT wants to build a cache.
610 The AT could cache the uniqueIDs in addition to other data being cached.
611 When an event is fired the AT could map the uniqueID to its internal model.
612 Thus, if there's a REORDER/SHOW/HIDE event the AT knows which part of the
613 internal structure has been invalidated and can refetch just that part.
614
615 This value can also be used by an AT to determine when the current control
616 has changed. If the role is the same for two controls that are adjacent in
617 the tab order, this can be used to detect the new control.
618
619 Another use of this value by an AT is to identify when a grouping object has
620 changed, e.g. when moving from a radio button in one group to a radio button in a
621 different group.
622
623 One means of implementing this would be to create a factory with a 32 bit number
624 generator and a reuse pool. The number generator would emit numbers starting
625 at 1. Each time an object's life cycle ended, its number would be saved into a
626 reuse pool. The number generator would be used whenever the reuse pool was empty.
627
628 Another way to create a unique ID is to generate it from a pointer value, e.g. an
629 object's address. That would be unique because no two active objects can use the
630 same allocated memory space.
631
632 @param [out] uniqueID
633 @retval S_OK
634 */
635 [propget] HRESULT uniqueID
636 (
637 [out, retval] long *uniqueID
638 );
639
640 /** @brief Returns the window handle for the parent window which contains this object.
641
642 This is the same window handle which will be passed for any events that occur on the
643 object, but is cached in the accessible object for use when it would be helpful to
644 access the window handle in cases where an event isn't fired on this object.
645
646 A use case is when a screen reader is grabbing an entire web page on a page load.
647 Without the availability of windowHandle, the AT would have to get the window handle
648 by using WindowFromAccessibleObject on each IAccessible, which is slow because it's
649 implemented by oleacc.dll as a loop which crawls up the ancestor chain and looks for
650 a ROLE_WINDOW object, mapping that back to a window handle.
651
652 @param [out] windowHandle
653 @retval S_OK
654 */
655 [propget] HRESULT windowHandle
656 (
657 [out, retval] HWND *windowHandle
658 );
659
660 /** @brief Returns the index of this object in its parent object.
661 @param [out] indexInParent
662 0 based; -1 indicates there is no parent; the upper bound is the value
663 returned by the parent's IAccessible::get_accChildCount.
664 @retval S_OK
665 @retval S_FALSE if no parent, [out] value is -1
666 */
667 [propget] HRESULT indexInParent
668 (
669 [out, retval] long *indexInParent
670 );
671
672 /** @brief Returns the IA2Locale of the accessible object.
673 @param [out] locale
674 @retval S_OK
675 */
676 [propget] HRESULT locale
677 (
678 [out, retval] IA2Locale *locale
679 );
680
681 /** @brief Returns the attributes specific to this object, such as a cell's formula.
682 @param [out] attributes
683 @retval S_OK
684 @retval S_FALSE returned if there is nothing to return, [out] value is NULL
685 */
686 [propget] HRESULT attributes
687 (
688 [out, retval] BSTR *attributes
689 );
690
691 }
692

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