accessible/interfaces/nsIAccessiblePivot.idl

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "nsISupports.idl"
   8
   9 typedef short PivotMoveReason;
  10
  11 interface nsIAccessible;
  12 interface nsIAccessibleTraversalRule;
  13
  14 /**
  15  * The pivot interface encapsulates a reference to a single place in an accessible
  16  * subtree. The pivot is a point or a range in the accessible tree. This interface
  17  * provides traversal methods to move the pivot to next/prev state that complies
  18  * to a given rule.
  19  */
  20 [scriptable, uuid(81fe5144-059b-42db-bd3a-f6ce3158d5e9)]
  21 interface nsIAccessiblePivot : nsISupports
  22 {
  23   /**
  24    * Move pivot to next object, from current position or given anchor,
  25    * complying to given traversal rule.
  26    *
  27    * @param aRule            [in] traversal rule to use.
  28    * @param aAnchor          [in] accessible to start search from, if not provided,
  29    *                           current position will be used.
  30    * @param aIncludeStart    [in] include anchor accessible in search.
  31    * @return next accessible node that matches rule in preorder.
  32    */
  33   [optional_argc] nsIAccessible next(in nsIAccessible aAnchor,
  34                                      in nsIAccessibleTraversalRule aRule,
  35                                      [optional] in boolean aIncludeStart);
  36
  37   /**
  38    * Move pivot to previous object, from current position or given anchor,
  39    * complying to given traversal rule.
  40    *
  41    * @param aRule            [in] traversal rule to use.
  42    * @param aAnchor          [in] accessible to start search from, if not provided,
  43    *                           current position will be used.
  44    * @param aIncludeStart    [in] include anchor accessible in search.
  45    * @return previous accessible node that matches rule in preorder.
  46    */
  47   [optional_argc] nsIAccessible prev(in nsIAccessible aAnchor,
  48                                      in nsIAccessibleTraversalRule aRule,
  49                                      [optional] in boolean aIncludeStart);
  50
  51   /**
  52    * Move pivot to first object in subtree complying to given traversal rule.
  53    *
  54    * @param aRule            [in] traversal rule to use.
  55    * @return first accessible node in subtree that matches rule in preorder.
  56    */
  57   nsIAccessible first(in nsIAccessibleTraversalRule aRule);
  58
  59   /**
  60    * Move pivot to last object in subtree complying to given traversal rule.
  61    *
  62    * @param aRule            [in] traversal rule to use.
  63    * @return last accessible node in subtree that matches rule in preorder.
  64    */
  65   nsIAccessible last(in nsIAccessibleTraversalRule aRule);
  66
  67   /**
  68    * Move pivot to given coordinate in screen pixels.
  69    *
  70    * @param aX               [in]  screen's x coordinate
  71    * @param aY               [in]  screen's y coordinate
  72    * @param aRule            [in]  raversal rule to use.
  73    * @return highest accessible in subtree that matches rule at given point.
  74    */
  75   nsIAccessible atPoint(in long aX, in long aY,
  76                         in nsIAccessibleTraversalRule aRule);
  77 };
  78
  79 [scriptable, uuid(e197460d-1eff-4247-b4bb-a43be1840dae)]
  80 interface nsIAccessibleTraversalRule : nsISupports
  81 {
  82   /* Ignore this accessible object */
  83   const unsigned short FILTER_IGNORE = 0x0;
  84   /* Accept this accessible object */
  85   const unsigned short FILTER_MATCH = 0x1;
  86   /* Don't traverse accessibles children */
  87   const unsigned short FILTER_IGNORE_SUBTREE = 0x2;
  88
  89   /**
  90    * Determines if a given accessible is to be accepted in our traversal rule
  91    *
  92    * @param aAccessible [in] accessible to examine.
  93    * @return a bitfield of FILTER_MATCH and FILTER_IGNORE_SUBTREE.
  94    */
  95   unsigned short match(in nsIAccessible aAccessible);
  96 };