Detect and receive notification of more iOS accessibility features

Adds following methods for detecting iOS accessibility features:
MobileAccessibility.isGuidedAccessEnabled()
MobileAccessibility.isInvertColorsEnabled()
MobileAccessibility.isGuidedAccessEnabled()
MobileAccessibility.isInvertColorsEnabled()
MobileAccessibility.isMonoAudioEnabled()

Adds corresponding window events to subscribe to notifications of
accessibility feature status updates:
“guidedaccessstatusdidchange”,
"invertcolorsstatusdidchange”,
"monoaudiostatusdidchange"

Adds following method for posting a notification as a string to be
announced by VoiceOver:
MobileAccessibility.postAnnouncementNotification()

www/mobile-accessibility.js

@@ -1,4 +1,4 @@
-/*
+cordova.define("com.phonegap.plugin.mobile-accessibility.mobile-accessibility", function(require, exports, module) {/*
  *
  * Licensed to the Apache Software Foundation (ASF) under one
  * or more contributor license agreements.  See the NOTICE file
@@ -26,58 +26,132 @@ var argscheck = require('cordova/argscheck'),
 var MobileAccessibility = function() {
     this._isVoiceOverRunning = false;
     this._isClosedCaptioningEnabled = false;
+    this._isGuidedAccessEnabled = false;
+    this._isInvertColorsEnabled = false;
+    this._isMonoAudioEnabled = false;
     // Create new event handlers on the window (returns a channel instance)
     this.channels = {
         voiceoverstatuschanged:cordova.addWindowEventHandler("voiceoverstatuschanged"),
-        closedcaptioningstatusdidchange:cordova.addWindowEventHandler("closedcaptioningstatusdidchange")
+        closedcaptioningstatusdidchange:cordova.addWindowEventHandler("closedcaptioningstatusdidchange"),
+        guidedaccessstatusdidchange:cordova.addWindowEventHandler("guidedaccessstatusdidchange"),
+        invertcolorsstatusdidchange:cordova.addWindowEventHandler("invertcolorsstatusdidchange"),
+        monoaudiostatusdidchange:cordova.addWindowEventHandler("monoaudiostatusdidchange")
     };
     for (var key in this.channels) {
         this.channels[key].onHasSubscribersChange = MobileAccessibility.onHasSubscribersChange;
     }
 };
-
+        
+/**
+ * @private
+ * @ignore
+ */
 function handlers() {
     return mobileAccessibility.channels.voiceoverstatuschanged.numHandlers +
-           mobileAccessibility.channels.closedcaptioningstatusdidchange.numHandlers;
+           mobileAccessibility.channels.closedcaptioningstatusdidchange.numHandlers +
+           mobileAccessibility.channels.invertcolorsstatusdidchange.numHandlers +
+           mobileAccessibility.channels.monoaudiostatusdidchange.numHandlers +
+           mobileAccessibility.channels.guidedaccessstatusdidchange.numHandlers;
 };
 
 /**
+ *
  * Event handlers for when callbacks get registered for mobileAccessibility.
  * Keep track of how many handlers we have so we can start and stop the native MobileAccessibility listener
  * appropriately.
+ * @private
+ * @ignore
  */
 MobileAccessibility.onHasSubscribersChange = function() {
     // If we just registered the first handler, make sure native listener is started.
     if (this.numHandlers === 1 && handlers() === 1) {
+               console.log("MobileAccessibility.onHasSubscribersChange "+handlers());
         exec(mobileAccessibility._status, mobileAccessibility._error, "MobileAccessibility", "start", []);
     } else if (handlers() === 0) {
         exec(null, null, "MobileAccessibility", "stop", []);
     }
 };
 
+/**
+ * Asynchronous call to native MobileAccessibility detemine if VoiceOver is running.
+ * @param {function} callback A callback method to recieve the asynchronous result from the native MobileAccessibility.
+ */
 MobileAccessibility.prototype.isVoiceOverRunning = function(callback) {
     exec(callback, null, "MobileAccessibility", "isVoiceOverRunning", []);
 };
 
+/**
+ * Asynchronous call to native MobileAccessibility to detemine if closed captioning is enabled.
+ * @param {function} callback A callback method to recieve the asynchronous result from the native MobileAccessibility.
+ */
 MobileAccessibility.prototype.isClosedCaptioningEnabled = function(callback) {
     exec(callback, null, "MobileAccessibility", "isClosedCaptioningEnabled", []);
 };
 
 /**
- * Callback for mobileAccessibility status
+ * Asynchronous call to native MobileAccessibility to detemine if the display colors have been inverted.
+ * @param {function} callback A callback method to recieve the asynchronous result from the native MobileAccessibility.
+ */
+MobileAccessibility.prototype.isInvertColorsEnabled = function(callback) {
+    exec(callback, null, "MobileAccessibility", "isInvertColorsEnabled", []);
+};
+
+/**
+ * Asynchronous call to native MobileAccessibility to detemine if mono audio is enabled.
+ * @param {function} callback A callback method to recieve the asynchronous result from the native MobileAccessibility.
+ */
+MobileAccessibility.prototype.isMonoAudioEnabled = function(callback) {
+    exec(callback, null, "MobileAccessibility", "isMonoAudioEnabled", []);
+};
+
+/**
+ * Asynchronous call to native MobileAccessibility to detemine if Guided Access is enabled.
+ * @param {function} callback A callback method to recieve the asynchronous result from the native MobileAccessibility.
+ */
+MobileAccessibility.prototype.isGuidedAccessEnabled = function(callback) {
+    exec(callback, null, "MobileAccessibility", "isGuidedAccessEnabled", []);
+};
+
+/**
+ * Posts an announcement notification with a string for VoiceOver to announce, if it is running.
+ * @param {string} string A string to be announced by VoiceOver.
+ * @param {function} callback A callback method to recieve the asynchronous result from the native MobileAccessibility, when the announcement is finished, the function should expect an object containing the stringValue that was voiced and a boolean indicating that the announcement wasSuccessful.
+ */
+MobileAccessibility.prototype.postAnnouncementNotification = function(string, callback) {
+    exec(callback, null, "MobileAccessibility", "postAnnouncementNotification", [string]);
+};
+
+/**
+ * Callback from native MobileAccessibility returning an which describes the status of iOS accessibility features.
  *
- * @param {Object} info keys: isVoiceOverRunning, isClosedCaptioningEnabled
+ * @param {Object} info
+ * @config {Boolean} [isVoiceOverRunning] Boolean to indicate VoiceOver status.
+ * @config {Boolean} [isClosedCaptioningEnabled] Boolean to indicate closed captioning status.
+ * @config {Boolean} [isGuidedAccessEnabled] Boolean to indicate guided access status.
+ * @config {Boolean} [isInvertColorsEnabled] Boolean to indicate invert colors status.
+ * @config {Boolean} [isMonoAudioEnabled] Boolean to indicate mono audio status.
  */
 MobileAccessibility.prototype._status = function(info) {
     if (info) {
-        var me = mobileAccessibility;
-        if (me._isVoiceOverRunning !== info.isVoiceOverRunning) {
+        if (mobileAccessibility._isVoiceOverRunning !== info.isVoiceOverRunning) {
             cordova.fireWindowEvent("voiceoverstatuschanged", info);
-            me._isVoiceOverRunning = info.isVoiceOverRunning;
+            mobileAccessibility._isVoiceOverRunning = info.isVoiceOverRunning;
         }
-        if (me._isClosedCaptioningEnabled !== info.isClosedCaptioningEnabled) {
+        if (mobileAccessibility._isClosedCaptioningEnabled !== info.isClosedCaptioningEnabled) {
             cordova.fireWindowEvent("closedcaptioningstatusdidchange", info);
-            me._isClosedCaptioningEnabled = info.isClosedCaptioningEnabled;
+            mobileAccessibility._isClosedCaptioningEnabled = info.isClosedCaptioningEnabled;
+        }
+        if (mobileAccessibility._isGuidedAccessEnabled !== info.isGuidedAccessEnabled) {
+            cordova.fireWindowEvent("guidedaccessstatusdidchange", info);
+            mobileAccessibility._isGuidedAccessEnabled = info.isGuidedAccessEnabled;
+        }
+        if (mobileAccessibility._isInvertColorsEnabled !== info.isInvertColorsEnabled) {
+            cordova.fireWindowEvent("invertcolorsstatusdidchange", info);
+            mobileAccessibility._isInvertColorsEnabled = info.isInvertColorsEnabled;
+        }
+        if (mobileAccessibility._isMonoAudioEnabled !== info.isMonoAudioEnabled) {
+           cordova.fireWindowEvent("monoaudiostatusdidchange", info);
+           mobileAccessibility._isMonoAudioEnabled = info.isMonoAudioEnabled;
         }
     }
 };
@@ -92,4 +166,4 @@ MobileAccessibility.prototype._error = function(e) {
 var mobileAccessibility = new MobileAccessibility();
                
 module.exports = mobileAccessibility;
-start
+});