accessible/public/nsIAccessible.idl

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   2 /* ***** BEGIN LICENSE BLOCK *****
   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
   5  * The contents of this file are subject to the Mozilla Public License Version
   6  * 1.1 (the "License"); you may not use this file except in compliance with
   7  * the License. You may obtain a copy of the License at
   8  * http://www.mozilla.org/MPL/
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  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
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  14  *
  15  * The Original Code is mozilla.org code.
  16  *
  17  * The Initial Developer of the Original Code is
  18  * Netscape Communications Corporation.
  19  * Portions created by the Initial Developer are Copyright (C) 2003
  20  * the Initial Developer. All Rights Reserved.
  21  *
  22  * Original Author: Eric D Vaughan (evaughan@netscape.com)
  23  * Contributor(s): Aaron Leventhal (aaronl@netscape.com)
  24  *                 John Gaunt (jgaunt@netscape.com)
  25  *                 Kyle Yuan (kyle.yuan@sun.com)
  26  *                 Håkan Waara (hwaara@gmail.com)
  27  *
  28  * Alternatively, the contents of this file may be used under the terms of
  29  * either the GNU General Public License Version 2 or later (the "GPL"), or
  30  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  31  * in which case the provisions of the GPL or the LGPL are applicable instead
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  37  * the provisions above, a recipient may use your version of this file under
  38  * the terms of any one of the MPL, the GPL or the LGPL.
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  40  * ***** END LICENSE BLOCK ***** */
  41
  42 #include "nsISupports.idl"
  43 #include "nsIArray.idl"
  44
  45 interface nsIPersistentProperties;
  46 interface nsIDOMDOMStringList;
  47 interface nsIAccessibleRelation;
  48
  49 /**
  50  * A cross-platform interface that supports platform-specific
  51  * accessibility APIs like MSAA and ATK. Contains the sum of what's needed
  52  * to support IAccessible as well as ATK's generic accessibility objects.
  53  * Can also be used by in-process accessibility clients to get information
  54  * about objects in the accessible tree. The accessible tree is a subset of
  55  * nodes in the DOM tree -- such as documents, focusable elements and text.
  56  * Mozilla creates the implementations of nsIAccessible on demand.
  57  * See http://www.mozilla.org/projects/ui/accessibility for more information.
  58  */
  59 [scriptable, uuid(c81d8f8c-8585-4094-bc7c-71dd01494906)]
  60 interface nsIAccessible : nsISupports
  61 {
  62   /**
  63    * Parent node in accessible tree.
  64    */
  65   readonly attribute nsIAccessible parent;
  66
  67   /**
  68    * Next sibling in accessible tree
  69    */
  70   readonly attribute nsIAccessible nextSibling;
  71
  72   /**
  73    * Previous sibling in accessible tree
  74    */
  75   readonly attribute nsIAccessible previousSibling;
  76
  77   /**
  78    * First child in accessible tree
  79    */
  80   readonly attribute nsIAccessible firstChild;
  81
  82   /**
  83    * Last child in accessible tree
  84    */
  85   readonly attribute nsIAccessible lastChild;
  86
  87   /**
  88    * Array of all this element's children.
  89    */
  90   readonly attribute nsIArray children;
  91
  92   /**
  93    * Number of accessible children
  94    */
  95   readonly attribute long childCount;
  96
  97   /**
  98    * The 0-based index of this accessible in its parent's list of children,
  99    * or -1 if this accessible does not have a parent.
 100    */
 101   readonly attribute long indexInParent;
 102
 103   /**
 104    * Accessible name -- the main text equivalent for this node. The name is
 105    * specified by ARIA or by native markup. Example of ARIA markup is
 106    * aria-labelledby attribute placed on element of this accessible. Example
 107    * of native markup is HTML label linked with HTML element of this accessible.
 108    *
 109    * Value can be string or null. A null value indicates that AT may attempt to
 110    * compute the name. Any string value, including the empty string, should be
 111    * considered author-intentional, and respected.
 112    */
 113   attribute AString name;
 114
 115   /**
 116    * Accessible value -- a number or a secondary text equivalent for this node
 117    * Widgets that use role attribute can force a value using the valuenow attribute
 118    */
 119   readonly attribute AString value;
 120
 121   /**
 122    * Accessible description -- long text associated with this node
 123    */
 124   readonly attribute AString description;
 125
 126   /**
 127    * Provides localized string of accesskey name, such as Alt+D.
 128    * The modifier may be affected by user and platform preferences.
 129    * Usually alt+letter, or just the letter alone for menu items.
 130    */
 131   readonly attribute AString keyboardShortcut;
 132
 133   /**
 134    * Provides localized string of global keyboard accelerator for default
 135    * action, such as Ctrl+O for Open file
 136    */
 137   readonly attribute AString defaultKeyBinding;
 138
 139   /**
 140    * Provides array of localized string of global keyboard accelerator for
 141    * the given action index supported by accessible.
 142    *
 143    * @param aActionIndex - index of the given action
 144    */
 145   nsIDOMDOMStringList getKeyBindings(in PRUint8 aActionIndex);
 146
 147   /**
 148    * Enumerated accessible role (see the constants defined in nsIAccessibleRole).
 149    *
 150    * @note  The values might depend on platform because of variations. Widgets
 151    *        can use ARIA role attribute to force the final role.
 152    */
 153   readonly attribute unsigned long role;
 154
 155   /**
 156    * Accessible states -- bit fields which describe boolean properties of node.
 157    * Many states are only valid given a certain role attribute that supports
 158    * them.
 159    *
 160    * @param aState - the first bit field (see nsIAccessibleStates::STATE_*
 161    *                 constants)
 162    * @param aExtraState - the second bit field
 163    *                      (see nsIAccessibleStates::EXT_STATE_* constants)
 164    */
 165   void getState(out unsigned long aState, out unsigned long aExtraState);
 166
 167   /**
 168    * Help text associated with node
 169    */
 170   readonly attribute AString help;
 171
 172   /**
 173    * Focused accessible child of node
 174    */
 175   readonly attribute nsIAccessible focusedChild;
 176
 177   /**
 178    * Attributes of accessible
 179    */
 180   readonly attribute nsIPersistentProperties attributes;
 181
 182   /**
 183    * Returns grouping information. Used for tree items, list items, tab panel
 184    * labels, radio buttons, etc. Also used for collectons of non-text objects.
 185    *
 186    * @param groupLevel - 1-based, similar to ARIA 'level' property
 187    * @param similarItemsInGroup - 1-based, similar to ARIA 'setsize' property,
 188    *                              inclusive of the current item
 189    * @param positionInGroup - 1-based, similar to ARIA 'posinset' property
 190    */
 191   void groupPosition(out long aGroupLevel, out long aSimilarItemsInGroup,
 192                      out long aPositionInGroup);
 193
 194   /**
 195    * Accessible child which contains the coordinate at (x, y) in screen pixels.
 196    * If the point is in the current accessible but not in a child, the
 197    * current accessible will be returned.
 198    * If the point is in neither the current accessible or a child, then
 199    * null will be returned.
 200    *
 201    * @param x  screen's x coordinate
 202    * @param y  screen's y coordinate
 203    * @return   the deepest accessible child containing the given point
 204    */
 205   nsIAccessible getChildAtPoint(in long x, in long y);
 206
 207   /**
 208    * Deepest accessible child which contains the coordinate at (x, y) in screen
 209    * pixels. If the point is in the current accessible but not in a child, the
 210    * current accessible will be returned. If the point is in neither the current
 211    * accessible or a child, then null will be returned.
 212    *
 213    * @param x  screen's x coordinate
 214    * @param y  screen's y coordinate
 215    * @return   the deepest accessible child containing the given point
 216    */
 217   nsIAccessible getDeepestChildAtPoint(in long x, in long y);
 218
 219   /**
 220    * Nth accessible child using zero-based index or last child if index less than zero
 221    */
 222   nsIAccessible getChildAt(in long aChildIndex);
 223
 224   /**
 225    * Accessible node geometrically to the right of this one
 226    */
 227   nsIAccessible getAccessibleToRight();
 228
 229   /**
 230    * Accessible node geometrically to the left of this one
 231    */
 232   nsIAccessible getAccessibleToLeft();
 233
 234   /**
 235    * Accessible node geometrically above this one
 236    */
 237   nsIAccessible getAccessibleAbove();
 238
 239   /**
 240    * Accessible node geometrically below this one
 241    */
 242   nsIAccessible getAccessibleBelow();
 243
 244   /**
 245    * Return accessible relation by the given relation type (see.
 246    * constants defined in nsIAccessibleRelation).
 247    */
 248   nsIAccessibleRelation getRelationByType(in unsigned long aRelationType);
 249
 250   /**
 251    * Returns the number of accessible relations for this object.
 252    */
 253   readonly attribute unsigned long relationsCount;
 254
 255   /**
 256    * Returns one accessible relation for this object.
 257    *
 258    * @param index - relation index (0-based)
 259    */
 260   nsIAccessibleRelation getRelation(in unsigned long index);
 261
 262   /**
 263    * Returns multiple accessible relations for this object.
 264    */
 265   nsIArray getRelations();
 266
 267   /**
 268    * Return accessible's x and y coordinates relative to the screen and
 269    * accessible's width and height.
 270    */
 271   void getBounds(out long x, out long y, out long width, out long height);
 272
 273   /**
 274    * Add or remove this accessible to the current selection
 275    */
 276   void setSelected(in boolean isSelected);
 277
 278   /**
 279    * Extend the current selection from its current accessible anchor node
 280    * to this accessible
 281    */
 282   void extendSelection();
 283
 284   /**
 285    * Select this accessible node only
 286    */
 287   void takeSelection();
 288
 289   /**
 290    * Focus this accessible node,
 291    * The state STATE_FOCUSABLE indicates whether this node is normally focusable.
 292    * It is the callers responsibility to determine whether this node is focusable.
 293    * accTakeFocus on a node that is not normally focusable (such as a table),
 294    * will still set focus on that node, although normally that will not be visually
 295    * indicated in most style sheets.
 296    */
 297   void takeFocus();
 298
 299   /**
 300    * The number of accessible actions associated with this accessible
 301    */
 302   readonly attribute PRUint8 numActions;
 303
 304   /**
 305    * The name of the accessible action at the given zero-based index
 306    */
 307   AString getActionName(in PRUint8 index);
 308
 309   /**
 310    * The description of the accessible action at the given zero-based index
 311    */
 312   AString getActionDescription(in PRUint8 aIndex);
 313
 314   /**
 315    * Perform the accessible action at the given zero-based index
 316    * Action number 0 is the default action
 317    */
 318   void doAction(in PRUint8 index);
 319
 320   /**
 321    * Get a pointer to accessibility interface for this node, which is specific
 322    * to the OS/accessibility toolkit we're running on.
 323    */
 324   [noscript] void getNativeInterface(out voidPtr aOutAccessible);
 325 };
 326