function XHRRequest (item) {
		this.AbstractRequest_constructor(item);

		// protected properties
		/**
		 * A reference to the XHR request used to load the content.
		 * @property _request
		 * @type {XMLHttpRequest | XDomainRequest | ActiveX.XMLHTTP}
		 * @private
		 */
		this._request = null;

		/**
		 * A manual load timeout that is used for browsers that do not support the onTimeout event on XHR (XHR level 1,
		 * typically IE9).
		 * @property _loadTimeout
		 * @type {Number}
		 * @private
		 */
		this._loadTimeout = null;

		/**
		 * The browser's XHR (XMLHTTPRequest) version. Supported versions are 1 and 2. There is no official way to detect
		 * the version, so we use capabilities to make a best guess.
		 * @property _xhrLevel
		 * @type {Number}
		 * @default 1
		 * @private
		 */
		this._xhrLevel = 1;

		/**
		 * The response of a loaded file. This is set because it is expensive to look up constantly. This property will be
		 * null until the file is loaded.
		 * @property _response
		 * @type {mixed}
		 * @private
		 */
		this._response = null;

		/**
		 * The response of the loaded file before it is modified. In most cases, content is converted from raw text to
		 * an HTML tag or a formatted object which is set to the <code>result</code> property, but the developer may still
		 * want to access the raw content as it was loaded.
		 * @property _rawResponse
		 * @type {String|Object}
		 * @private
		 */
		this._rawResponse = null;

		this._canceled = false;

		// Setup our event handlers now.
		this._handleLoadStartProxy = createjs.proxy(this._handleLoadStart, this);
		this._handleProgressProxy = createjs.proxy(this._handleProgress, this);
		this._handleAbortProxy = createjs.proxy(this._handleAbort, this);
		this._handleErrorProxy = createjs.proxy(this._handleError, this);
		this._handleTimeoutProxy = createjs.proxy(this._handleTimeout, this);
		this._handleLoadProxy = createjs.proxy(this._handleLoad, this);
		this._handleReadyStateChangeProxy = createjs.proxy(this._handleReadyStateChange, this);

		if (!this._createXHR(item)) {
			//TODO: Throw error?
		}
	}
A preloader that loads items using XHR requests, usually XMLHttpRequest. However XDomainRequests will be used
for cross-domain requests if possible, and older versions of IE fall back on to ActiveX objects when necessary.
XHR requests load the content as text or binary data, provide progress and consistent completion events, and
can be canceled during load. Note that XHR is not supported in IE 6 or earlier, and is not recommended for
cross-domain loading.
@class XHRRequest
@constructor
@param {Object} item The object that defines the file to load. Please see the {{#crossLink "LoadQueue/loadFile"}}{{/crossLink}}
for an overview of supported file properties.
@extends AbstractLoader