Update wmts-hidpi, add nicer-api-docs

nicer-api-docs/closure-library/closure/goog/a11y/aria/announcer.js

@@ -0,0 +1,108 @@
+// Copyright 2007 The Closure Library Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS-IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+
+/**
+ * @fileoverview Announcer that allows messages to be spoken by assistive
+ * technologies.
+ */
+
+goog.provide('goog.a11y.aria.Announcer');
+
+goog.require('goog.Disposable');
+goog.require('goog.a11y.aria');
+goog.require('goog.a11y.aria.LivePriority');
+goog.require('goog.a11y.aria.State');
+goog.require('goog.dom');
+goog.require('goog.object');
+
+
+
+/**
+ * Class that allows messages to be spoken by assistive technologies that the
+ * user may have active.
+ *
+ * @param {goog.dom.DomHelper=} opt_domHelper DOM helper.
+ * @constructor
+ * @extends {goog.Disposable}
+ */
+goog.a11y.aria.Announcer = function(opt_domHelper) {
+  goog.base(this);
+
+  /**
+   * @type {goog.dom.DomHelper}
+   * @private
+   */
+  this.domHelper_ = opt_domHelper || goog.dom.getDomHelper();
+
+  /**
+   * Map of priority to live region elements to use for communicating updates.
+   * Elements are created on demand.
+   * @type {Object.<goog.a11y.aria.LivePriority, Element>}
+   * @private
+   */
+  this.liveRegions_ = {};
+};
+goog.inherits(goog.a11y.aria.Announcer, goog.Disposable);
+
+
+/** @override */
+goog.a11y.aria.Announcer.prototype.disposeInternal = function() {
+  goog.object.forEach(
+      this.liveRegions_, this.domHelper_.removeNode, this.domHelper_);
+  this.liveRegions_ = null;
+  this.domHelper_ = null;
+  goog.base(this, 'disposeInternal');
+};
+
+
+/**
+ * Announce a message to be read by any assistive technologies the user may
+ * have active.
+ * @param {string} message The message to announce to screen readers.
+ * @param {goog.a11y.aria.LivePriority=} opt_priority The priority of the
+ *     message. Defaults to POLITE.
+ */
+goog.a11y.aria.Announcer.prototype.say = function(message, opt_priority) {
+  goog.dom.setTextContent(this.getLiveRegion_(
+      opt_priority || goog.a11y.aria.LivePriority.POLITE), message);
+};
+
+
+/**
+ * Returns an aria-live region that can be used to communicate announcements.
+ * @param {!goog.a11y.aria.LivePriority} priority The required priority.
+ * @return {Element} A live region of the requested priority.
+ * @private
+ */
+goog.a11y.aria.Announcer.prototype.getLiveRegion_ = function(priority) {
+  if (this.liveRegions_[priority]) {
+    return this.liveRegions_[priority];
+  }
+  var liveRegion;
+  liveRegion = this.domHelper_.createElement('div');
+  // Note that IE has a habit of declaring things that aren't display:none as
+  // invisible to third-party tools like JAWs, so we can't just use height:0.
+  liveRegion.style.position = 'absolute';
+  liveRegion.style.top = '-1000px';
+  liveRegion.style.height = '1px';
+  liveRegion.style.overflow = 'hidden';
+  goog.a11y.aria.setState(liveRegion, goog.a11y.aria.State.LIVE,
+      priority);
+  goog.a11y.aria.setState(liveRegion, goog.a11y.aria.State.ATOMIC,
+      'true');
+  this.domHelper_.getDocument().body.appendChild(liveRegion);
+  this.liveRegions_[priority] = liveRegion;
+  return liveRegion;
+};