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diff --git a/src/3rdparty/iaccessible2/idl/Accessible2.idl b/src/3rdparty/iaccessible2/idl/Accessible2.idl new file mode 100644 index 0000000000..6a0d750483 --- /dev/null +++ b/src/3rdparty/iaccessible2/idl/Accessible2.idl @@ -0,0 +1,679 @@ +/************************************************************************* + * + * File Name (Accessible2.idl) + * + * IAccessible2 IDL Specification + * + * Copyright (c) 2007, 2010 Linux Foundation + * Copyright (c) 2006 IBM Corporation + * Copyright (c) 2000, 2006 Sun Microsystems, Inc. + * All rights reserved. + * + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * 2. Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * 3. Neither the name of the Linux Foundation nor the names of its + * contributors may be used to endorse or promote products + * derived from this software without specific prior written + * permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND + * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, + * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE + * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR + * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; + * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR + * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, + * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * This BSD License conforms to the Open Source Initiative "Simplified + * BSD License" as published at: + * http://www.opensource.org/licenses/bsd-license.php + * + * IAccessible2 is a trademark of the Linux Foundation. The IAccessible2 + * mark may be used in accordance with the Linux Foundation Trademark + * Policy to indicate compliance with the IAccessible2 specification. + * + ************************************************************************/ + +/** @mainpage + + @section _interfaces Interfaces + IAccessible2\n + IAccessibleAction\n + IAccessibleApplication\n + IAccessibleComponent\n + IAccessibleHypertext\n + IAccessibleHyperlink\n + IAccessibleImage\n + IAccessibleRelation\n + IAccessibleTable [Deprecated]\n + IAccessibleTable2\n + IAccessibleTableCell\n + IAccessibleText\n + IAccessibleEditableText\n + IAccessibleValue + + @section _structs Structs + IA2Locale\n + IA2TableModelChange\n + IA2TextSegment + + @section _enums Enums + ::IA2CoordinateType values define the requested coordinate type (screen or parent window).\n + ::IA2EventID values identify events.\n + ::IA2Role values defines roles which are in addition to the existing MSAA roles.\n + ::IA2ScrollType values define where to place an object or substring on the screen.\n + ::IA2States values define states which are in addition to the existing MSAA states.\n + ::IA2TableModelChangeType values describe the kinds of changes made to a table (insert, delete, update).\n + ::IA2TextBoundaryType values define the requested text unit (character, word, sentence, line, paragraph).\n + ::IA2TextSpecialOffsets values define special offsets for use in the text interfaces. + + @section _constants Constants + @ref grpRelations + + @section _misc Miscellaneous + @ref _licensePage "BSD License"\n + @ref _generalInfo "General Information"\n + + @page _licensePage BSD License + %IAccessible2 IDL Specification + + Copyright (c) 2007, 2010 Linux Foundation\n + Copyright (c) 2006 IBM Corporation\n + Copyright (c) 2000, 2006 Sun Microsystems, Inc.\n + All rights reserved. + + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions + are met: + + 1. Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + + 2. Redistributions in binary form must reproduce the above + copyright notice, this list of conditions and the following + disclaimer in the documentation and/or other materials + provided with the distribution. + + 3. Neither the name of the Linux Foundation nor the names of its + contributors may be used to endorse or promote products + derived from this software without specific prior written + permission. + + THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND + CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, + INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE + DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR + CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; + LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR + OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, + EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + + This BSD License conforms to the Open Source Initiative "Simplified + BSD License" as published at: + http://www.opensource.org/licenses/bsd-license.php + + %IAccessible2 is a trademark of the Linux Foundation. The %IAccessible2 + mark may be used in accordance with the + <a href="http://www.linuxfoundation.org/collaborate/workgroups/accessibility/trademark-policy"> + Linux Foundation Trademark Policy</a> to indicate compliance with the %IAccessible2 specification. + + @page _generalInfo General Information + The following information is applicable to two or more interfaces. + + @ref _errors\n + @ref _memory\n + @ref _arrayConsideration\n + @ref _indexes\n + @ref _enums\n + @ref _specialOffsets\n + @ref _dicoveringInterfaces\n + @ref _changingInterfaces\n + @ref _applicationInfo\n + @ref _childIDs\n + @ref _variants\n + @ref _iaaction-iahyperlink\n + @ref _trademark + + @section _errors Error Handling + HRESULT values are defined by the Microsoft® Win32® API. For more information, refer to + <a href="http://msdn2.microsoft.com/en-us/library/bb401631.aspx">Interpreting HRESULT Values</a> + in MSDN®. + + Note that the S_FALSE return value is considered a non-error value and the + SUCCEEDED macro will return TRUE. S_FALSE is used when there is no failure + but there was nothing valid to return, e.g. in IAccessible2::attributes when + there are no attributes. When S_FALSE is returned [out] pointer types should + be NULL and [out] longs should generally be 0, but sometimes -1 is used such + as IAccessible2::indexInParent, IAccessibleText::caretOffset, and + IAccessibleHypertext::hyperlinkIndex. + + Note that for BSTR [out] variables common COM practice is that the server does + the SysAllocString and the client does the SysFreeString. Also note that when + NULL is returned there is no need for the client to call SysFreeString. Please + refer to the documentation for each method for more details regarding error handling. + + @section _memory Memory Management + The following memory management issues should be considered: + @li Although [out] BSTR variables are declared by the client, their space is + allocated by the server. They need to be freed with SysFreeString by the + client at end of life; the same is true when BSTRs are used in structs or + arrays which are passed to the server. + @li If there is no valid [out] BSTR to return, the server should return S_FALSE and + assign NULL to the output, e.g. *theOutBSTR = NULL;. + @li COM interfaces need to be referenced with AddRef when used and dereferenced + with Release at end of life. + @li Single [out] longs, HWNDs, booleans, and structs are declared by the caller + and passed by reference. The marshaller does all the memory management. + + The following articles may be helpful for understanding memory management issues: + @li An article by Don Box in a + <a href="http://www.microsoft.com/msj/1196/activex1196.aspx">Q & A section</a> + of the November 1996 edition of the Microsoft Systems Journal. + @li A posting to a CodeGuru forum, + <a href="http://www.codeguru.com/forum/showthread.php?t=364511">Windows SDK + String: What are the rules for BSTR allocation and deallocation?</a> + + @subsection _arrayConsideration Special Consideration when using Arrays + There are several methods which return arrays. In the case of IAccessible2::relations + and IAccessibleRelation::targets the client must allocate and free the arrays. + + For the remaining methods which return arrays, the server must allocate the array + and the client must free the array when no longer needed. These methods are + IAccessible2::extendedStates, IAccessible2::localizedExtendedStates, + IAccessibleAction::keyBinding, IAccessibleTable2::selectedCells, + IAccessibleTable2::selectedColumns, and IAccessibleTable2::selectedRows. For + those methods, the server must allocate both the top level array and any storage + associated with it, e.g. for BSTRs. The server must allocate the arrays with + CoTaskMemAlloc and any BSTRs with SysAllocString. The client must use CoTaskMemFree + to free the array and any BSTRs must be freed with SysFreeString. + + Also, the IDL for those six methods includes an extraneous [in] parameter for the + caller to specify the max size of the array. This parameter will be ignored by + the COM server. + + @section _indexes Zero and One Based Indexes + Unless otherwise specified all offsets and indexes are 0 based. + + @section _enums Enums + Note that enums start at 0. + + @section _specialOffsets Special Offsets for use in the IAccessibleText and IAccessibleEditableText Methods + IAccessibleText and IAccessibleEditableText can use one or more of the following + special offset values. They are defined in the ::IA2TextSpecialOffsets enum. + @li Using ::IA2_TEXT_OFFSET_LENGTH (-1) as an offset in any of the IAccessibleText or + IAccessibleEditableText methods is the same as specifying the length of the string. + @li Using ::IA2_TEXT_OFFSET_CARET (-2) as an offset for IAccessibleText::textBeforeOffset, + IAccessibleText::textAtOffset, and IAccessibleText::textAfterOffset indicates that the + text related to the physical location of the caret should be used. This is needed for + applications that consider the character offset of the end of one line (as reached by + pressing the End key) the same as the offset of the first character on the next line. + Since the same offset is associated with two different lines a special means is needed + to fetch text from the line where the caret is physically located. + + @section _dicoveringInterfaces Discovery of Interfaces + In general AT (Assistive Technology) should try IAccessible2 interfaces, followed by using + the MSAA (Microsoft® Active Accessibility®) interfaces. (In cases where the an application + is known to have custom interfaces which provide information not supplied by IAccessible2 + or MSAA, then those custom interfaces can be used.) The AT can then, by default, support + unknown IAccessible2/MSAA applications, without the application developers having to request + AT vendors for support on an individual application by application basis. + + When you have a reference to an IAccessible and require a reference to an IAccessible2 use + QueryService as follows: + @code + // pAcc is a reference to the accessible object's IAccessible interface. + IServiceProvider *pService = NULL; + hr = pAcc->QueryInterface(IID_IServiceProvider, (void **)&pService); + if(SUCCEEDED(hr)) { + IAccessible2 *pIA2 = NULL; + hr = pService->QueryService(IID_IAccessible, IID_IAccessible2, (void**)&pIA2); + if (SUCCEEDED(hr) && pIA2) { + // The control supports IAccessible2. + // pIA2 is the reference to the accessible object's IAccessible2 interface. + } + } + @endcode + + @section _changingInterfaces Changing between Accessible Interfaces + Note that developers must always implement MSAA's IAccessible and, if needed, some + of the interfaces in the set of IAccessible2 interfaces. Although the IAccessible2 + IDL is coded such that IAccessible2 is a subclass of MSAA's IAccessible, none of + MSAA's IAccessible methods are redefined by IAccessible2. + + QueryService must be used to switch from a reference to an MSAA IAccessible interface + to another interface. This has been + <a href="http://www.accessinteropalliance.org/docs/Introducing_IAccessibleEx.doc"> + documented by Microsoft</a> and the pertinent facts have been extracted below: + + @par + Why use QueryService instead of just using QueryInterface to get IAccessibleEx + directly? The reason is that since MSAA 2.0, clients don't talk to a server's + IAccessible interface directly; instead they talk to an intermediate MSAA-provided + wrapper that calls through to the original IAccessible. This wrapper provides services + such as implementing IDispatch, supplying information from MSAA 2.0's Dynamic Annotation + service, and scaling locations when running on Windows Vista with DPI scaling enabled. + QueryService is the supported way to expose additional interfaces from an existing + IAccessible and was originally used by MSHTML to expose IHTMLElement objects corresponding + to IAccessibles. QueryService is often more convenient for servers to implement than + QueryInterface because it does not have the same requirements for preserving object + identity or symmetry/transitivity as QueryInterface, so QueryService allows servers to + easily implement the interface on the same object or a separate object. The latter is + often hard to do with QueryInterface unless the original object supports aggregation. + + Two related references in MSDN® are: + @li <a href="http://msdn.microsoft.com/en-us/library/ms696078(VS.85).aspx"> + "Using QueryService to expose a native object model interface for an IAccessible object"</a> + @li <a href="http://msdn.microsoft.com/en-us/library/ms528415.aspx#acc_obj"> + "Accessing the Internet Explorer Object Associated with an Accessible Object"</a> + + Based on this information from Microsoft, QueryService must be used to switch back and forth + between a reference to an MSAA IAccessible interface and any of the IAccessible2 interfaces. + + Regarding switching between any of the IAccessible2 interfaces, applications implementing + IAccessible2 should implement the IAccessible2 interfaces on a single object since ATs + will be using QueryInterface to switch between the IAccessilbe2 interfaces. Implementing + the IAccessible2 interfaces on separate objects would require the use of QueryService. + There is one exception, IAccessibleApplication can be implemented on a separate object so + its common code doesn't have to be included in each accessible object. ATs should use + QueryService to access IAccessibleApplication. + + @section _applicationInfo Access to Information about the Application + Servers implementing IAccessible2 should provide access to the IAccessibleApplication + interface via QueryService from any object so that ATs can easily determine specific + information about the application such as its name or version. + + @section _childIDs Child IDs + The IAccessible2 interfaces do not support child IDs, i.e. simple child elements. + Full accessible objects must be created for each object that supports IAccessible2. + Therefore MSAA's get_accChild should never return a child ID (other than CHILDID_SELF) + for an object that implements any of the IAccessible2 interfaces. + + Microsoft's UI Automation specification has the same limitation and this was resolved + in the UI Automation Express specification by adding IAccessibleEx::GetObjectForChild + and IAccessibleEx::GetIAccessiblePair. These methods allow mapping back and forth + between an IAccessibleEx and an {IAccessible, Child ID} pair. A future version of + IAccessible2 may include similar methods to map back and forth between an IAccessible2 + and an {IAccessible, Child ID} pair. + + @section _variants VARIANTs + Some methods return a VARIANT. Implementers need to make sure that the return type is + specified, i.e. VT_I4, VT_IDISPATCH, etc. The methods that return VARIANTs are + IAccessibleHyperlink::anchor, IAccessibleHyperlink::anchorTarget, IAccessibleValue::currentValue, + IAccessibleValue::maximumValue, IAccessibleValue::minimumValue. + + @section _iaaction-iahyperlink IAccessibleHyperlink as subclass of IAccessibleAction + In this version of the IDL, IAccessibleHyperlink is a subclass of IAccessibleAction. + However, there is no practical need for that inheritance and in some cases, such as + an image map of smart tags, it doesn't make sense because such an image map doesn't + have actionable objects; it's the secondary smart tags that are actionable. As a + result, implementations should not rely on the inheritance as it may be removed in + a later version of the IDL. + + @section _trademark Trademark Attribution + The names of actual companies and products mentioned herein may be the trademarks of + their respective owners. In particular, Active Accessibility, Microsoft, MSDN, and Win32 + are trademarks of the Microsoft group of companies in the U.S.A. and/or other countries. + +**/ + +import "objidl.idl"; +import "oaidl.idl"; +import "oleacc.idl"; +import "AccessibleRelation.idl"; +import "AccessibleStates.idl"; +import "IA2CommonTypes.idl"; + +/** A structure defining the locale of an accessible object. + +IAccessible2::locale returns this struct. +*/ +typedef struct IA2Locale { + BSTR language; ///< ISO 639-1 Alpha-2 two character language code + BSTR country; ///< ISO 3166-1 Alpha-2 two character country code + BSTR variant; ///< Application specific variant of the locale +} IA2Locale; + +/** @brief This interface exposes the primary set of information about an + IAccessible2 enabled accessible object. + + This interface must always be provided for objects that support some + portion of the collection of the %IAccessible2 interfaces. + + Please refer to @ref _changingInterfaces "Changing between Accessible Interfaces" + for special considerations related to use of the MSAA IAccessible interface and + the set of %IAccessible2 interfaces. + */ +[object, uuid(E89F726E-C4F4-4c19-BB19-B647D7FA8478)] +interface IAccessible2 : IAccessible +{ + + /** @brief Returns the number of accessible relations for this object. + @param [out] nRelations + @retval S_OK + */ + [propget] HRESULT nRelations + ( + [out, retval] long *nRelations + ); + + /** @brief Returns one accessible relation for this object. + @param [in] relationIndex + 0 based + @param [out] relation + @retval S_OK + @retval E_INVALIDARG if bad [in] passed + */ + [propget] HRESULT relation + ( + [in] long relationIndex, + [out, retval] IAccessibleRelation **relation + ); + + /** @brief Returns multiple accessible relations for this object. + @param [in] maxRelations + maximum size of the array allocated by the client + @param [out] relations + The array of accessible relation objects. Note that this array is to be + allocated by the client and freed when no longer needed. Refer to @ref + _arrayConsideration "Special Consideration when using Arrays" for more details. + @param [out] nRelations + actual number of relations in the returned array (not more than maxRelations) + @retval S_OK + @retval S_FALSE if there are no relations, nRelations is set to 0 + */ + [propget] HRESULT relations + ( + [in] long maxRelations, + [out, size_is(maxRelations), length_is(*nRelations)] + IAccessibleRelation **relations, + [out, retval] long *nRelations + ); + + /** @brief Returns the role of an %IAccessible2 object. + @param [out] role + The role of an %IAccessible2 object. + @retval S_OK + @note + @li For convenience MSAA roles are also passed through this method so the + AT doesn't have to also fetch roles through MSAA's get_accRole. + @li %IAccessible2 roles should not be passed through MSAA's get_accRole. + @li For compatibility with non IAccessible2 enabled ATs, IAccessible2 + applications should also add support to get_accRole to return the closest + MSAA role or ROLE_SYSTEM_CLIENT (the MSAA defined default role) if there + is not a good match. + @li This method is missing a [propget] prefix in the IDL. The result is the + method is named role in generated C++ code instead of get_role. + */ + HRESULT role + ( + [out, retval] long *role + ); + + /** @brief Makes an object visible on the screen. + @param [in] scrollType + Defines where the object should be placed on the screen. + @retval S_OK + @retval E_INVALIDARG if bad [in] passed + */ + HRESULT scrollTo + ( + [in] enum IA2ScrollType scrollType + ); + + /** @brief Moves the top left of an object to a specified location. + + @param [in] coordinateType + Specifies whether the coordinates are relative to the screen or the parent object. + @param [in] x + Defines the x coordinate. + @param [in] y + Defines the y coordinate. + @retval S_OK + @retval E_INVALIDARG if bad [in] passed + */ + HRESULT scrollToPoint + ( + [in] enum IA2CoordinateType coordinateType, + [in] long x, + [in] long y + ); + + /** @brief Returns grouping information. + + Used for tree items, list items, tab panel labels, radio buttons, etc. + Also used for collections of non-text objects. + + @param [out] groupLevel + 1 based, 0 indicates that this value is not applicable + @param [out] similarItemsInGroup + 1 based, 0 indicates that this value is not applicable + @param [out] positionInGroup + 1 based, 0 indicates that this value is not applicable. This is an index + into the objects in the current group, not an index into all the objects + at the same group level. + @retval S_OK if at least one value is valid + @retval S_FALSE if no values are valid, [out] values are 0s + @note This method is meant to describe the nature of an object's containment + structure. It's exposed by trees, tree grids, nested lists, nested menus, + but not headings, which uses the level object attribute. It is also exposed + by radio buttons (with groupLevel == 0). + @note This is normally not implemented on a combo box to describe the nature + of its contents. Normally an AT will get that information from its child list + object. However, in some cases when non-edit combo boxes are not able to be structured + such that the list is a child of the combo box, this method is implemented on + the combo box itself. ATs can use this interface if a child list is not found. + */ + [propget] HRESULT groupPosition + ( + [out] long *groupLevel, + [out] long *similarItemsInGroup, + [out, retval] long *positionInGroup + ); + + /** @brief Returns the bit strip containing any IAccessible2 states. + + The IAccessible2 states are in addition to the MSAA states and are defined in + the IA2States enum. + + @param [out] states + @retval S_OK + */ + [propget] HRESULT states + ( + [out, retval] AccessibleStates *states + ); + + /** @brief Returns the extended role. + + An extended role is a role which is dynamically generated by the application. + It is not predefined by the %IAccessible2 specification. + + @param [out] extendedRole + @retval S_OK + @retval S_FALSE if there is nothing to return, [out] value is NULL + */ + [propget] HRESULT extendedRole + ( + [out, retval] BSTR *extendedRole + ); + + /** @brief Returns the localized extended role. + @param [out] localizedExtendedRole + @retval S_OK + @retval S_FALSE if there is nothing to return, [out] value is NULL + */ + [propget] HRESULT localizedExtendedRole + ( + [out, retval] BSTR *localizedExtendedRole + ); + + /** @brief Returns the number of extended states. + @param [out] nExtendedStates + @retval S_OK + */ + [propget] HRESULT nExtendedStates + ( + [out, retval] long *nExtendedStates + ); + + /** @brief Returns the extended states (array of strings). + + An extended state is a state which is dynamically generated by the application. + It is not predefined by the %IAccessible2 specification. + + @param [in] maxExtendedStates + This parameter is ignored. Refer to @ref _arrayConsideration + "Special Consideration when using Arrays" for more details. + @param [out] extendedStates + This array is allocated by the server. Free it with CoTaskMemFree. + @param [out] nExtendedStates + The number of extended states returned; the size of the returned array. + @retval S_OK + @retval S_FALSE if there are no states, [out] values are NULL and 0 respectively + */ + [propget] HRESULT extendedStates + ( + [in] long maxExtendedStates, + [out, size_is(,maxExtendedStates), length_is(,*nExtendedStates)] BSTR **extendedStates, + [out, retval] long *nExtendedStates + ); + + /** @brief Returns the localized extended states (array of strings). + @param [in] maxLocalizedExtendedStates + This parameter is ignored. Refer to @ref _arrayConsideration + "Special Consideration when using Arrays" for more details. + @param [out] localizedExtendedStates + This array is allocated by the server. Free it with CoTaskMemFree. + @param [out] nLocalizedExtendedStates + The number of localized extended states returned; the size of the returned array. + @retval S_OK + @retval S_FALSE if there are no states, [out] values are NULL and 0 respectively + */ + [propget] HRESULT localizedExtendedStates + ( + [in] long maxLocalizedExtendedStates, + [out, size_is(,maxLocalizedExtendedStates), length_is(,*nLocalizedExtendedStates)] BSTR **localizedExtendedStates, + [out, retval] long *nLocalizedExtendedStates + ); + + /** @brief Returns the unique ID. + + The uniqueID is an identifier for this object, is unique within the + current window, and remains the same for the lifetime of the accessible + object. + + The uniqueID is not related to: + - the MSAA objectID which is used by the server to disambiguate between + IAccessibles per HWND or + - the MSAA childID which is used to disambiguate between children being + managed by an IAccessible. + + This value is provided so the AT can have access to a unique runtime persistent + identifier even when not handling an event for the object. + + An example of when this value is useful is if the AT wants to build a cache. + The AT could cache the uniqueIDs in addition to other data being cached. + When an event is fired the AT could map the uniqueID to its internal model. + Thus, if there's a REORDER/SHOW/HIDE event the AT knows which part of the + internal structure has been invalidated and can refetch just that part. + + This value can also be used by an AT to determine when the current control + has changed. If the role is the same for two controls that are adjacent in + the tab order, this can be used to detect the new control. + + Another use of this value by an AT is to identify when a grouping object has + changed, e.g. when moving from a radio button in one group to a radio button in a + different group. + + One means of implementing this would be to create a factory with a 32 bit number + generator and a reuse pool. The number generator would emit numbers starting + at 1. Each time an object's life cycle ended, its number would be saved into a + reuse pool. The number generator would be used whenever the reuse pool was empty. + + Another way to create a unique ID is to generate it from a pointer value, e.g. an + object's address. That would be unique because no two active objects can use the + same allocated memory space. + + @param [out] uniqueID + @retval S_OK + */ + [propget] HRESULT uniqueID + ( + [out, retval] long *uniqueID + ); + + /** @brief Returns the window handle for the parent window which contains this object. + + This is the same window handle which will be passed for any events that occur on the + object, but is cached in the accessible object for use when it would be helpful to + access the window handle in cases where an event isn't fired on this object. + + A use case is when a screen reader is grabbing an entire web page on a page load. + Without the availability of windowHandle, the AT would have to get the window handle + by using WindowFromAccessibleObject on each IAccessible, which is slow because it's + implemented by oleacc.dll as a loop which crawls up the ancestor chain and looks for + a ROLE_WINDOW object, mapping that back to a window handle. + + @param [out] windowHandle + @retval S_OK + */ + [propget] HRESULT windowHandle + ( + [out, retval] HWND *windowHandle + ); + + /** @brief Returns the index of this object in its parent object. + @param [out] indexInParent + 0 based; -1 indicates there is no parent; the upper bound is the value + returned by the parent's IAccessible::get_accChildCount. + @retval S_OK + @retval S_FALSE if no parent, [out] value is -1 + */ + [propget] HRESULT indexInParent + ( + [out, retval] long *indexInParent + ); + + /** @brief Returns the IA2Locale of the accessible object. + @param [out] locale + @retval S_OK + */ + [propget] HRESULT locale + ( + [out, retval] IA2Locale *locale + ); + + /** @brief Returns the attributes specific to this %IAccessible2 object, such as a cell's formula. + @param [out] attributes + @retval S_OK + @retval S_FALSE returned if there is nothing to return, [out] value is NULL + */ + [propget] HRESULT attributes + ( + [out, retval] BSTR *attributes + ); + +} + |