Complete live region support in ChromeVox Next.

chrome/common/extensions/api/automation.idl

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // The <code>chrome.automation</code> API allows developers to access the
 // automation (accessibility) tree for the browser. The tree resembles the DOM
 // tree, but only exposes the <em>semantic</em> structure of a page. It can be
 // used to programmatically interact with a page by examining names, roles, and
 // states, listening for events, and performing actions on nodes.
 [nocompile] namespace automation {
@@ skipping 299 matching lines @@
 
   // A change to the Automation tree.
   [nocompile, noinline_doc] dictionary TreeChange {
     // The $(ref:automation.AutomationNode) that changed.
     AutomationNode target;
 
     // The type of change.
     TreeChangeType type;
   };
 
+  // Possible tree changes to listen to using addTreeChangeObserver.
+  // Note that listening to all tree changes can be expensive.
+  enum TreeChangeObserverFilter {
+    noTreeChanges,
+    liveRegionTreeChanges,
+    allTreeChanges
+  };
+
   // A listener for changes on the <code>AutomationNode</code> tree.
   callback TreeChangeObserver = void(TreeChange treeChange);
 
   // A single node in an Automation tree.
   [nocompile, noinline_doc] dictionary AutomationNode {
     // The root node of the tree containing this AutomationNode.
     AutomationNode root;
 
     // Whether this AutomationNode is a root node.
     boolean isRootNode;
@@ skipping 157 matching lines @@
     // The number of columns that this cell spans (default is 1).
     long tableCellColumnSpan;
 
     // The zero-based index of the row that this cell is in.
     long tableCellRowIndex;
 
     // The number of rows that this cell spans (default is 1).
     long tableCellRowSpan;
 
     //
+    // Live region attributes.
+    //
+
+    // The type of region if this is the root of a live region.
+    // Possible values are 'polite' and 'assertive'.
+    DOMString liveStatus;
+
+    // The value of aria-relevant for a live region.
+    DOMString liveRelevant;
+
+    // The value of aria-atomic for a live region.
+    boolean liveAtomic;
+
+    // The value of aria-busy for a live region.
+    boolean liveBusy;
+
+    // The type of live region if this node is inside a live region.
+    DOMString containerLiveStatus;
+
+    // The value of aria-relevant if this node is inside a live region.
+    DOMString containerLiveRelevant;
+
+    // The value of aria-atomic if this node is inside a live region.
+    boolean containerLiveAtomic;
+
+    // The value of aria-busy if this node is inside a live region.
+    boolean containerLiveBusy;
+
+    //
     // Walking the tree.
     //
 
     AutomationNode[] children;
     AutomationNode parent;
     AutomationNode firstChild;
     AutomationNode lastChild;
     AutomationNode previousSibling;
     AutomationNode nextSibling;
 
@@ skipping 65 matching lines @@
     // tree with a placeholder root node; listen for the "loadComplete" event to
     // get a notification that the tree has fully loaded (the previous root node
     // reference will stop working at or before this point).
     [nocompile] static void getTree(optional long tabId, RootCallback callback);
 
     // Get the automation tree for the whole desktop which consists of all on
     // screen views. Note this API is currently only supported on Chrome OS.
     [nocompile] static void getDesktop(RootCallback callback);
 
     // Add a tree change observer. Tree change observers are static/global, they
-    // listen to changes across all trees.
+    // listen to changes across all trees. Pass a filter to determine what
+    // specific tree changes to listen to, and note that listnening to all
+    // tree changes can be expensive.
     [nocompile] static void addTreeChangeObserver(
-        TreeChangeObserver observer);
+        TreeChangeObserverFilter filter, TreeChangeObserver observer);
 
     // Remove a tree change observer.
     [nocompile] static void removeTreeChangeObserver(
         TreeChangeObserver observer);
 
     // Sets the selection in a tree. This creates a selection in a single
     // tree (anchorObject and focusObject must have the same root).
     // Everything in the tree between the two node/offset pairs gets included
     // in the selection. The anchor is where the user started the selection,
     // while the focus is the point at which the selection gets extended
     // e.g. when dragging with a mouse or using the keyboard. For nodes with
     // the role staticText, the offset gives the character offset within
     // the value where the selection starts or ends, respectively.
     [nocompile] static void setDocumentSelection(
         SetDocumentSelectionParams params);
   };
 };