remoting/webapp/suspend_monitor.js

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 /**
   6  * @fileoverview
   7  * Class to detect when the device is suspended, for example when a laptop's
   8  * lid is closed.
   9  */
  10
  11
  12 'use strict';
  13
  14 /** @suppress {duplicate} */
  15 var remoting = remoting || {};
  16
  17 /**
  18  * @param {function():void} callback Callback function to invoke when a
  19  * suspend+resume operation has been detected.
  20  *
  21  * @constructor
  22  */
  23 remoting.SuspendMonitor = function (callback) {
  24   /** @type {function():void} @private */
  25   this.callback_ = callback;
  26   /** @type {number} @private */
  27   this.timerIntervalMs_ = 60 * 1000;
  28   /** @type {number} @private */
  29   this.lateToleranceMs_ = 60 * 1000;
  30   /** @type {number} @private */
  31   this.callbackExpectedTime_ = 0;
  32   this.start_();
  33 };
  34
  35 /** @private */
  36 remoting.SuspendMonitor.prototype.start_ = function() {
  37   window.setTimeout(this.checkSuspend_.bind(this), this.timerIntervalMs_);
  38   this.callbackExpectedTime_ = new Date().getTime() + this.timerIntervalMs_;
  39 };
  40
  41 /** @private */
  42 remoting.SuspendMonitor.prototype.checkSuspend_ = function() {
  43   var lateByMs = new Date().getTime() - this.callbackExpectedTime_;
  44   if (lateByMs > this.lateToleranceMs_) {
  45     this.callback_();
  46   }
  47   this.start_();
  48 };
  49
  50 /** @type {remoting.SuspendMonitor?} */
  51 remoting.suspendMonitor = null;