Add vectortile branch
This commit is contained in:
@@ -0,0 +1,123 @@
|
||||
// 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.Timer');
|
||||
goog.require('goog.a11y.aria');
|
||||
goog.require('goog.a11y.aria.LivePriority');
|
||||
goog.require('goog.a11y.aria.State');
|
||||
goog.require('goog.dom');
|
||||
goog.require('goog.dom.TagName');
|
||||
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}
|
||||
* @final
|
||||
*/
|
||||
goog.a11y.aria.Announcer = function(opt_domHelper) {
|
||||
goog.a11y.aria.Announcer.base(this, 'constructor');
|
||||
|
||||
/**
|
||||
* @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.a11y.aria.Announcer.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) {
|
||||
var priority = opt_priority || goog.a11y.aria.LivePriority.POLITE;
|
||||
var liveRegion = this.getLiveRegion_(priority);
|
||||
// Resets text content to force a DOM mutation (so that the setTextContent
|
||||
// post-timeout function will be noticed by the screen reader). This is to
|
||||
// avoid the problem of when the same message is "said" twice, which doesn't
|
||||
// trigger a DOM mutation.
|
||||
goog.dom.setTextContent(liveRegion, '');
|
||||
// Uses non-zero timer to make VoiceOver and NVDA work
|
||||
goog.Timer.callOnce(function() {
|
||||
goog.dom.setTextContent(liveRegion, message);
|
||||
}, 1);
|
||||
};
|
||||
|
||||
|
||||
/**
|
||||
* 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) {
|
||||
var liveRegion = this.liveRegions_[priority];
|
||||
if (liveRegion) {
|
||||
// Make sure the live region is not aria-hidden.
|
||||
goog.a11y.aria.removeState(liveRegion, goog.a11y.aria.State.HIDDEN);
|
||||
return liveRegion;
|
||||
}
|
||||
|
||||
liveRegion = this.domHelper_.createElement(goog.dom.TagName.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;
|
||||
};
|
||||
Reference in New Issue
Block a user