other-licenses/ia2/AccessibleHyperlink.idl

   1 /*************************************************************************
   2  *
   3  *  File Name (AccessibleHyperlink.idl)
   4  *
   5  *  IAccessible2 IDL Specification
   6  *
   7  *  Copyright (c) Linux Foundation 2007, 2008
   8  *  Copyright (c) IBM Corp. 2006
   9  *  Copyright (c) Sun Microsystems, Inc. 2000, 2006
  10  *
  11  *  This library is free software; you can redistribute it and/or
  12  *  modify it under the terms of the GNU Lesser General Public
  13  *  License version 2.1, as published by the Free Software Foundation; either
  14  *  version 2.1 of the License, or (at your option) any later version.
  15  *
  16  *  This library is distributed in the hope that it will be useful,
  17  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19  *  Lesser General Public License for more details.
  20  *
  21  *  You should have received a copy of the GNU Lesser General Public
  22  *  License along with this library; if not, write to the Free Software
  23  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02110-1301  USA
  24  *
  25  ************************************************************************/
  26
  27 import "objidl.idl";
  28 import "oaidl.idl";
  29 import "oleacc.idl";
  30 import "AccessibleAction.idl";
  31
  32 /** @brief This interface represents hyperlinks.
  33
  34  This interface represents a hyperlink associated with a single substring
  35   of text or single non-text object.  Non-text objects can have either a
  36   single link or a collection of links such as when the non-text object is
  37   an image map.
  38
  39  Linked objects and anchors are implementation dependent. This interface is derived
  40   from IAccessibleAction.  IAccessibleAction::nActions is one greater than the
  41   maximum value for the indices used with the methods of this interface.
  42
  43  Furthermore, the object that implements this interface has to be connected
  44   implicitly or explicitly with an object that implements IAccessibleText.
  45   IAccessibleHyperlink::startIndex and IAccessibleHyperlink::endIndex are
  46   indices with respect to the text exposed by IAccessibleText.
  47
  48  This interface provides access to a single object which can have multiple actions.
  49   An example is an image map which is an image with multiple links each of which is
  50   associated with a separate non-overlapping area of the image.  This interface could
  51   also be applied to other kinds of objects with multiple actions such as "smart tags"
  52   which are objects, typically strings, which have multiple actions such as
  53   "Activate URI", "Bookmark URI", etc.
  54
  55  An interesting use case is an image map where each area is associated with multiple
  56   actions, e.g. an image map of smart tags.  In this case you would have to implement
  57   two levels of accessible hyperlinks.  The first level hyperlinks would only implement
  58   anchor and anchorTarget.  The anchors would all reference the image object.  The
  59   anchorTargets would reference the second level accessible hyperlink objects.  None
  60   of the IAccessibleAction methods would be implemented on the first level hyperlink
  61   objects.  The second level hyperlink objects would implement the IAccessibleAction
  62   methods.  Their anchors would also reference the image object and their anchorTargets
  63   would reference URLs or the objects that would be activated.
  64
  65  This use case demonstrates that in some cases there is no need for IAccessibleHyperlink
  66   to derive from IAccessibleAction.  As a result it may be removed in a later version of
  67   the IDL and it is suggested that implementations should not rely on the inheritance.
  68
  69 */
  70 [object, uuid(01C20F2B-3DD2-400f-949F-AD00BDAB1D41)]
  71 interface IAccessibleHyperlink : IAccessibleAction
  72 {
  73
  74   /** @brief Returns an object that represents the link anchor, as appropriate
  75    for the link at the specified index.
  76    @param [in] index
  77     A 0 based index identifies the anchor when, as in the case of an image map,
  78     there is more than one link represented by this object.  The valid maximal
  79     index is indicated by IAccessibleAction::nActions.
  80    @param [out] anchor
  81     This is an implementation dependent value.  For example, for a text link this
  82         method could return the substring of the containing string where the substring
  83         is overridden with link behavior, and for an image link this method could return
  84         an IUnknown VARIANT for IAccessibleImage.  See the section about
  85         @ref _variants "VARIANTs" for additional information.
  86    @retval S_OK
  87    @retval S_FALSE if there is nothing to return, [out] value is NULL
  88    @retval E_INVALIDARG if bad [in] passed, [out] value is NULL
  89   */
  90   [propget] HRESULT anchor
  91     (
  92      [in] long index,
  93      [out, retval] VARIANT *anchor
  94     );
  95
  96   /** @brief Returns an object representing the target of the link, as appropriate
  97    for the link at the specified index.
  98    @param [in] index
  99     A 0 based index identifies the anchor when, as in the case of an image map,
 100     there is more than one link represented by this object.  The valid maximal
 101     index is indicated by IAccessibleAction::nActions.
 102    @param [out] anchorTarget
 103     This is an implementation dependent value.  For example this method could
 104         return a BSTR VARIANT of the URI.  Alternatively this method could return an
 105         IUnknown VARIANT of a COM interface representing a target object to be
 106         activated when the link is activated.  See the section about
 107         @ref _variants "VARIANTs" for additional information.
 108    @retval S_OK
 109    @retval S_FALSE if there is nothing to return, [out] value is NULL
 110    @retval E_INVALIDARG if bad [in] passed, [out] value is NULL
 111   */
 112   [propget] HRESULT anchorTarget
 113     (
 114      [in] long index,
 115      [out, retval] VARIANT *anchorTarget
 116     );
 117
 118   /** @brief Returns the 0 based character offset at which the textual representation of the hyperlink starts.
 119
 120    The returned value is related to the IAccessibleText interface of the object that
 121    owns this hyperlink.
 122    @param [out] index
 123    @retval S_OK
 124   */
 125   [propget] HRESULT startIndex
 126     (
 127      [out, retval] long *index
 128     );
 129
 130   /** @brief Returns the 0 based character offset at which the textual representation of the hyperlink ends.
 131
 132    The returned value is related to the IAccessibleText interface of the object that
 133    owns this hyperlink. The character at the index is not part of the hypertext.
 134    @param [out] index
 135    @retval S_OK
 136   */
 137   [propget] HRESULT endIndex
 138     (
 139      [out, retval] long *index
 140     );
 141
 142   /** @brief Returns whether the target object referenced by this link is still valid.
 143
 144    This is a volatile state that may change without sending an appropriate event.
 145    Returns TRUE if the referenced target is still valid and FALSE otherwise.
 146
 147    This has also been used to indicate whether or not the URI of the anchorTarget
 148    is malformed.
 149
 150    Note: This method is not being used, is deprecated, and should not be implemented or
 151    used.  It is likely that this method will be removed in a later version of the IDL.
 152
 153    @param [out] valid
 154    @retval S_OK
 155    @retval S_FALSE if there is nothing to return, [out] value is FALSE
 156   */
 157   [propget] HRESULT valid
 158     (
 159      [out, retval] boolean *valid
 160     );
 161 }