Working proof of concept of select to speak

chrome/browser/resources/chromeos/chromevox/s2s/background/background.js

+// Copyright 2015 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.
+
+goog.provide('s2s.Background');
+goog.require('AutomationUtil');
+
+goog.scope(function() {
+var RoleType = chrome.automation.RoleType;
+
+s2s.Background = function() {
+  chrome.tts.speak('Select to speak');
+  this.spokenSelection_ = new s2s.SpokenSelection();
+};
+
+s2s.Background.prototype = {
+};
+
+s2s.SpokenSelection = function() {
+  this.node_ = null;
+  this.down_ = false;
+
+  chrome.automation.getDesktop(function(d) {
+    d.addEventListener('mousePressed', this.onMousePressed.bind(this), true);
+    d.addEventListener('mouseDragged', this.onMouseDragged.bind(this), true);
+    d.addEventListener('mouseMoved', this.onMouseDragged.bind(this), true);
+    d.addEventListener('mouseReleased', this.onMouseReleased.bind(this), true);
+  }.bind(this));
+};
+
+s2s.SpokenSelection.prototype = {
+  onMousePressed: function(evt) {
+    this.node_ = null;
+    this.down_ = true;
+    chrome.tts.stop();
+    this.onMouseDragged(evt);
+  },
+
+  onMouseDragged: function(evt) {
+    if (!this.down_)
+      return;
+
+    var node = evt.target;
+    if (!this.node_) {
+      while (node && !node.name)
+        node = node.parent;
+      this.node_ = node;
+    } else {
+      var a1 = AutomationUtil.getAncestors(this.node_);
+      var a2 = AutomationUtil.getAncestors(node);
+      var d = AutomationUtil.getDivergence(a1, a2);
+      if (d > 0) {
+        this.node_ = a1[d - 1];
+      }
+    }
+
+    chrome.accessibilityPrivate.setFocusRing([this.node_.location]);
+  },
+
+  onMouseReleased: function(evt) {
+    this.onMouseDragged(evt);
+    this.down_ = false;
+
+    if (!this.node_) {
+      chrome.accessibilityPrivate.setFocusRing([]);
+      return;
+    }
+
+    this.enqueue_ = false;
+    this.speakAllDescendants_(this.node_);
+
+    window.setTimeout(function() {
+      chrome.accessibilityPrivate.setFocusRing([]);
+    }, 1000);
+  },
+
+  speakAllDescendants_: function(node) {
+    if (this.node_.role == RoleType.inlineTextBox ||
+        this.node_.role == RoleType.staticText) {
+      chrome.tts.speak(node.name, {lang: 'en-US',
+                                   'enqueue': this.enqueue_});
+      this.enqueue_ = true;
+      return true;
+    }
+
+    var spoke = false;
+    for (var c = node.firstChild; c; c = c.nextSibling) {
+      if (this.speakAllDescendants_(c))
+        spoke = true;
+    }
+    if (!spoke && node.name) {
+      chrome.tts.speak(node.name, {lang: 'en-US',
+                                   'enqueue': this.enqueue_});
+      this.enqueue_ = true;
+      spoke = true;
+    }
+    return spoke;
+  }
+};
+
+new s2s.Background();
+
+});  // goog.scope