/************************************************************************* * * File Name (AccessibleText.idl) * * IAccessible2 IDL Specification * * Copyright (c) Linux Foundation 2007, 2008 * Copyright (c) IBM Corp. 2006 * Copyright (c) Sun Microsystems, Inc. 2000, 2006 * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License version 2.1, as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA * ************************************************************************/ import "objidl.idl"; import "oaidl.idl"; import "oleacc.idl"; import "IA2CommonTypes.idl"; /** A structure containing a substring and the start and end offsets in the enclosing string. IAccessibleText::newText and IAccessibleText::oldText return this struct. */ typedef struct IA2TextSegment { BSTR text; ///< A copy of a segment of text taken from an enclosing paragraph. long start; ///< Index of the first character of the segment in the enclosing text. long end; ///< Index of the character following the last character of the segment in the enclosing text. } IA2TextSegment; /** This enum defines values which specify a text boundary type. IA2_TEXT_BOUNDARY_SENTENCE is optional. When a method doesn't implement this method it must return S_FALSE. Typically this feature would not be implemented by an application. However, if the application developer was not satisfied with how screen readers have handled the reading of sentences this boundary type could be implemented and screen readers could use the application's version of a sentence rather than the screen reader's. The rest of the boundary types must be supported. This enum is used in IAccessibleText::textBeforeOffset, IAccessibleText::textAtOffset, and IAccessibleText::textAfterOffset. */ enum IA2TextBoundaryType { IA2_TEXT_BOUNDARY_CHAR, /**< Typically, a single character is returned. In some cases more than one character is returned, for example, when a document contains field data such as a field containing a date, time, or footnote reference. In this case the caret can move over several characters in one movement of the caret. Note that after the caret moves, the caret offset changes by the number of characters in the field, e.g. by 8 characters in the following date: 03/26/07. */ IA2_TEXT_BOUNDARY_WORD, /**< The range provided matches the range observed when the application processes the Ctrl + left arrow and Ctrl + right arrow key sequences. Typically this is from the start of one word to the start of the next, but various applications are inconsistent in the handling of the end of a line. */ IA2_TEXT_BOUNDARY_SENTENCE, ///< Range is from start of one sentence to the start of another sentence. IA2_TEXT_BOUNDARY_PARAGRAPH, ///< Range is from start of one paragraph to the start of another paragraph. IA2_TEXT_BOUNDARY_LINE, /**< Range is from start of one line to the start of another line. This often means that an end-of-line character will appear at the end of the range. However in the case of some applications an end-of-line character indicates the end of a paragraph and the lines composing the paragraph, other than the last line, do not contain an end of line character. */ IA2_TEXT_BOUNDARY_ALL ///< Using this value will cause all text to be returned. }; /** @brief This interface gives read-only access to text. The %IAccessibleText interface should be implemented by all components that present textual information on the display like buttons, text entry fields, or text portions of the document window. The interface provides access to the text's content, attributes, and spatial location. However, text can not be modified with this interface. That is the task of the IAccessibleEditableText interface. The text length, i.e. the number of characters in the text, is returned by IAccessibleText::nCharacters. All methods that operate on particular characters (e.g. IAccessibleText::textAtOffset) use character indices from 0 to length-1. All methods that operate on character positions (e.g. IAccessibleText::text) use indices from 0 to length. Please note that accessible text does not necessarily support selection. In this case it should behave as if there where no selection. An empty selection is used for example to express the current cursor position. Refer to @ref _specialOffsets "Special Offsets for use in the IAccessibleText and IAccessibleEditableText Methods" for information about special offsets that can be used in %IAccessibleText methods. E_FAIL is returned in the following cases @li endOffset < startOffset @li endoffset > length */ [object, uuid(24FD2FFB-3AAD-4a08-8335-A3AD89C0FB4B)] interface IAccessibleText : IUnknown { /** @brief Adds a text selection @param [in] startOffset Starting offset ( 0 based). @param [in] endOffset Offset of first character after new selection (0 based). @retval S_OK @retval E_INVALIDARG if bad [in] passed */ HRESULT addSelection ( [in] long startOffset, [in] long endOffset ); /** @brief Returns text attributes. @param [in] offset Text offset (0 based) @param [out] startOffset The starting offset of the character range over which all text attributes match those of offset. (0 based) @param [out] endOffset The offset of the first character past the character range over which all text attributes match those of offset. (0 based) @param [out] textAttributes A string of attributes describing the text. The attributes are described in the text attributes specification on the %IAccessible2 web site. @retval S_OK @retval S_FALSE if there is nothing to return, [out] values are 0s and NULL respectively @retval E_INVALIDARG if bad [in] passed, [out] values are 0s and NULL respectively */ [propget] HRESULT attributes ( [in] long offset, [out] long *startOffset, [out] long *endOffset, [out, retval] BSTR *textAttributes ); /** @brief Returns the position of the caret. Returns the 0-based offset of the caret within the text. If the text is implemented as a tree of text objects with embed characters in higher levels representing substrings of child text objects and the caret is in one of the child text objects, then the offset in the higher level text object would be at the embed character representing child text object that contains the caret. For example, if the string "one two three" is implemented as a two text objects, with a top level text object containing an embed character "one ? three" and a child text object containing "two" and if the caret is in the descendant object just before the 'o' in "two", then: The caret position/offset is that of the character logically following it, e.g. to the right of it in a left to right language. @param [out] offset The returned offset is relative to the text represented by this object. @retval S_OK @retval S_FALSE if the caret is not currently active on this object, i.e. the caret is located on some other object. The returned offset value will be -1. @note S_FALSE (and an offset of -1) will not be returned if the caret is somewhere in the text object or one of its descendants. */ [propget] HRESULT caretOffset ( [out, retval] long *offset ); /** @brief Returns the bounding box of the specified position. The virtual character after the last character of the represented text, i.e. the one at position length is a special case. It represents the current input position and will therefore typically be queried by AT more often than other positions. Because it does not represent an existing character its bounding box is defined in relation to preceding characters. It should be roughly equivalent to the bounding box of some character when inserted at the end of the text. Its height typically being the maximal height of all the characters in the text or the height of the preceding character, its width being at least one pixel so that the bounding box is not degenerate. Note that the index 'length' is not always valid. Whether it is or not is implementation dependent. It typically is when text is editable or otherwise when on the screen the caret can be placed behind the text. You can be sure that the index is valid after you have received a ::IA2_EVENT_TEXT_CARET_MOVED event for this index. @param [in] offset Index of the character for which to return its bounding box. The valid range is 0..length. @param [in] coordType Specifies if the coordinates are relative to the screen or to the parent window. @param [out] x X coordinate of the top left corner of the bounding box of the referenced character. @param [out] y Y coordinate of the top left corner of the bounding box of the referenced character. @param [out] width Width of the bounding box of the referenced character. @param [out] height Height of the bounding box of the referenced character. @retval S_OK @retval E_INVALIDARG if bad [in] passed, [out] values are 0s */ [propget] HRESULT characterExtents ( [in] long offset, [in] enum IA2CoordinateType coordType, [out] long *x, [out] long *y, [out] long *width, [out, retval] long *height ); /** @brief Returns the number of active non-contiguous selections @param [out] nSelections @retval S_OK */ [propget] HRESULT nSelections ( [out, retval] long *nSelections ); /** @brief Returns the text position for the specified screen position. Given a point return the zero-based index of the character under that point. The same functionality could be achieved by using the bounding boxes for each character as returned by IAccessibleText::characterExtents. The method IAccessibleText::offsetAtPoint, however, can be implemented more efficiently. @param [in] x The position's x value for which to look up the index of the character that is rendered on to the display at that point. @param [in] y The position's y value for which to look up the index of the character that is rendered on to the display at that point. @param [in] coordType Screen coordinates or window coordinates. @param [out] offset Index of the character under the given point or -1 if the point is invalid or there is no character under the point. @retval S_OK @retval E_INVALIDARG if bad [in] passed, [out] value is 0 */ [propget] HRESULT offsetAtPoint ( [in] long x, [in] long y, [in] enum IA2CoordinateType coordType, [out, retval] long *offset ); /** @brief Returns the character offsets of Nth active text selection @param [in] selectionIndex Index of selection (0 based). @param [out] startOffset 0 based offset of first selected character @param [out] endOffset 0 based offset of one past the last selected character. @retval S_OK @retval S_FALSE if there is nothing to return, [out] values are 0s @retval E_INVALIDARG if bad [in] passed, [out] values are 0s */ [propget] HRESULT selection ( [in] long selectionIndex, [out] long *startOffset, [out, retval] long *endOffset ); /** @brief Returns the substring between the two given indices. The substring starts with the character at startOffset (inclusive) and up to the character at endOffset (exclusive), if startOffset is less or equal endOffste. If endOffset is lower than startOffset, the result is the same as a call with the two arguments being exchanged. The whole text can be requested by passing the indices zero and IAccessibleText::nCharacters. If both indices have the same value, an empty string is returned. @param [in] startOffset Index of the first character to include in the returned string. The valid range is 0..length. @param [in] endOffset Index of the last character to exclude in the returned string. The valid range is 0..length. @param [out] text Returns the substring starting with the character at startOffset (inclusive) and up to the character at endOffset (exclusive), if startOffset is less than or equal to endOffset. @retval S_OK @retval E_INVALIDARG if bad [in] passed, [out] value is NULL @note The returned string may be longer than endOffset-startOffset bytes if text contains multi-byte characters. */ [propget] HRESULT text ( [in] long startOffset, [in] long endOffset, [out, retval] BSTR *text ); /** @brief Returns a text portion before the given position. Returns the substring of the specified text type that is located before the given character and does not include it. The result of this method should be same as a result for IAccessibleText::textAtOffset with a suitably decreased index value. For example, if text type is ::IA2_TEXT_BOUNDARY_WORD, then the complete word that is closest to and located before offset is returned. If the index is valid, but no suitable word (or other boundary type) is found, a NULL pointer is returned. @param [in] offset Index of the character for which to return the text part before it. The index character will not be part of the returned string. The valid range is 0..length. @param [in] boundaryType The type of the text portion to return. See ::IA2TextBoundaryType for the complete list. @param [out] startOffset 0 based offset of first character. @param [out] endOffset 0 based offset of one past the last character. @param [out] text Returns the requested text portion. This portion may be empty or invalid when no appropriate text portion is found or text type is invalid. @retval S_OK @retval S_FALSE if the requested boundary type is not implemented, such as ::IA2_TEXT_BOUNDARY_SENTENCE, or if there is nothing to return; [out] values are 0s and NULL respectively @retval E_INVALIDARG if bad [in] passed, [out] values are 0s and NULL respectively */ [propget] HRESULT textBeforeOffset ( [in] long offset, [in] enum IA2TextBoundaryType boundaryType, [out] long *startOffset, [out] long *endOffset, [out, retval] BSTR *text ); /** @brief Returns a text portion after the given position. Returns the substring of the specified text type that is located after the given character and does not include it. The result of this method should be same as a result for IAccessibleText::textAtOffset with a suitably increased index value. For example, if text type is ::IA2_TEXT_BOUNDARY_WORD, then the complete word that is closest to and located after offset is returned. If the index is valid, but no suitable word (or other text type) is found, a NULL pointer is returned. @param [in] offset Index of the character for which to return the text part before it. The index character will not be part of the returned string. The valid range is 0..length. @param [in] boundaryType The type of the text portion to return. See ::IA2TextBoundaryType for the complete list. @param [out] startOffset 0 based offset of first character. @param [out] endOffset 0 based offset of one past the last character. @param [out] text Returns the requested text portion. This portion may be empty or invalid when no appropriate text portion is found or text type is invalid. @retval S_OK @retval S_FALSE if the requested boundary type is not implemented, such as ::IA2_TEXT_BOUNDARY_SENTENCE, or if there is nothing to return; [out] values are 0s and NULL respectively @retval E_INVALIDARG if bad [in] passed, [out] values are 0s and NULL respectively */ [propget] HRESULT textAfterOffset ( [in] long offset, [in] enum IA2TextBoundaryType boundaryType, [out] long *startOffset, [out] long *endOffset, [out, retval] BSTR *text ); /** @brief Returns a text portion that spans the given position. Returns the substring of the specified text type at the specified offset. If the index is valid, but no suitable word (or other text type) is found, a NULL pointer is returned. @param [in] offset Index of the character for which to return the text part before it. The index character will not be part of the returned string. The valid range is 0..length. @param [in] boundaryType The type of the text portion to return. See ::IA2TextBoundaryType for the complete list. @param [out] startOffset 0 based offset of first character. @param [out] endOffset 0 based offset of one past the last character. @param [out] text Returns the requested text portion. This portion may be empty or invalid when no appropriate text portion is found or text type is invalid. @retval S_OK @retval S_FALSE if the requested boundary type is not implemented, such as ::IA2_TEXT_BOUNDARY_SENTENCE, or if there is nothing to return; [out] values are 0s and NULL respectively @retval E_INVALIDARG if bad [in] passed, [out] values are 0s and NULL respectively */ [propget] HRESULT textAtOffset ( [in] long offset, [in] enum IA2TextBoundaryType boundaryType, [out] long *startOffset, [out] long *endOffset, [out, retval] BSTR *text ); /** @brief Unselects a range of text. @param [in] selectionIndex Index of selection to remove (0 based). @retval S_OK @retval E_INVALIDARG if bad [in] passed */ HRESULT removeSelection ( [in] long selectionIndex ); /** @brief Sets the position of the caret. The caret position/offset is that of the character logically following it, e.g. to the right of it in a left to right language. Setting the caret position may or may not alter the current selection. A change of the selection is notified to the accessibility event listeners with an ::IA2_EVENT_TEXT_SELECTION_CHANGED event. When the new caret position differs from the old one (which, of course, is the standard case) this is notified to the accessibility event listeners with an ::IA2_EVENT_TEXT_CARET_MOVED event. @param [in] offset The new index of the caret. This caret is actually placed to the left side of the character with that index. An index of 0 places the caret so that the next insertion goes before the first character. An index of IAccessibleText::nCharacters leads to insertion after the last character. @retval S_OK @retval E_FAIL if the caret cannot be set @retval E_INVALIDARG if bad [in] passed */ HRESULT setCaretOffset ( [in] long offset ); /** @brief Changes the bounds of an existing selection. @param [in] selectionIndex Index of selection to change (0 based) @param [in] startOffset New starting offset (0 based) @param [in] endOffset New ending offset (0 based) - the offset of the character just past the last character of the selection. @retval S_OK @retval E_INVALIDARG if bad [in] passed */ HRESULT setSelection ( [in] long selectionIndex, [in] long startOffset, [in] long endOffset ); /** @brief Returns total number of characters. Note that this may be different than the total number of bytes required to store the text, if the text contains multi-byte characters. @param [out] nCharacters @retval S_OK */ [propget] HRESULT nCharacters ( [out, retval] long *nCharacters ); /** @brief Makes a specific part of string visible on screen. @param [in] startIndex 0 based character offset. @param [in] endIndex 0 based character offset - the offset of the character just past the last character of the string. @param [in] scrollType Defines where the object should be placed on the screen. @retval S_OK @retval E_INVALIDARG if bad [in] passed */ HRESULT scrollSubstringTo ( [in] long startIndex, [in] long endIndex, [in] enum IA2ScrollType scrollType ); /** @brief Moves the top left of a substring to a specified location. @param [in] startIndex 0 based character offset. @param [in] endIndex 0 based character offset - the offset of the character just past the last character of the string. @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 S_FALSE if the object is already at the specified location. @retval E_INVALIDARG if bad [in] passed */ HRESULT scrollSubstringToPoint ( [in] long startIndex, [in] long endIndex, [in] enum IA2CoordinateType coordinateType, [in] long x, [in] long y ); /** @brief Returns any inserted text. Provided for use by the ::IA2_EVENT_TEXT_INSERTED and ::IA2_EVENT_TEXT_UPDATED event handlers. This data is only guaranteed to be valid while the thread notifying the event continues. Once the handler has returned, the validity of the data depends on how the server manages the life cycle of its objects. Also, note that the server may have different life cycle management strategies for controls depending on whether or not a control manages its children. Lists, trees, and tables can have a large number of children and thus it's possible that the child objects for those controls would only be created as needed. Servers should document their life cycle strategy as this will be of interest to assistive technology or script engines accessing data out of process or from other threads. Servers only need to save the last inserted block of text and a scope of the entire application is adequate. @param [out] newText The text that was just inserted. @retval S_OK @retval S_FALSE if there is nothing to return, [out] value is NULL */ [propget] HRESULT newText ( [out, retval] IA2TextSegment *newText ); /** @brief Returns any removed text. Provided for use by the IA2_EVENT_TEXT_REMOVED/UPDATED event handlers. This data is only guaranteed to be valid while the thread notifying the event continues. Once the handler has returned, the validity of the data depends on how the server manages the life cycle of its objects. Also, note that the server may have different life cycle management strategies for controls depending on whether or not a control manages its children. Lists, trees, and tables can have a large number of children and thus it's possible that the child objects for those controls would only be created as needed. Servers should document their life cycle strategy as this will be of interest to assistive technology or script engines accessing data out of process or from other threads. Servers only need to save the last removed block of text and a scope of the entire application is adequate. @param [out] oldText The text that was just removed. @retval S_OK @retval S_FALSE if there is nothing to return, [out] value is NULL */ [propget] HRESULT oldText ( [out, retval] IA2TextSegment *oldText ); }