gerrit/files/static/jquery-visibility.js

/*!
 * jquery-visibility v1.0.12
 * Page visibility shim for jQuery.
 *
 * Project Website: http://mths.be/visibility
 * 
 * @version 1.0.12
 * @license MIT.
 * @author Mathias Bynens - @mathias
 * @author Jan Paepke - @janpaepke
 */
;(function (root, factory) {
    if (typeof define === 'function' && define.amd) {
        // AMD. Register as an anonymous module.
        define(['jquery'], function ($) {
            return factory(root, $);
        });
    } else if (typeof exports === 'object') {
        // Node/CommonJS
        module.exports = factory(root, require('jquery'));
    } else {
        // Browser globals
        factory(root, jQuery);
    }
}(typeof window !== 'undefined' ? window : this, function(window, $, undefined) {
    "use strict";

    var
        document = window.document,
        property, // property name of document, that stores page visibility
        vendorPrefixes = ['webkit', 'o', 'ms', 'moz', ''],
        $support = $.support || {},
        // In Opera, `'onfocusin' in document == true`, hence the extra `hasFocus` check to detect IE-like behavior
        eventName = 'onfocusin' in document && 'hasFocus' in document ?
            'focusin focusout' :
            'focus blur';

    var prefix;
    while ((prefix = vendorPrefixes.pop()) !== undefined) {
        property = (prefix ? prefix + 'H': 'h') + 'idden';
        $support.pageVisibility = document[property] !== undefined;
        if ($support.pageVisibility) {
            eventName = prefix + 'visibilitychange';
            break;
        }
    }

    // normalize to and update document hidden property
    function updateState() {
        if (property !== 'hidden') {
            document.hidden = $support.pageVisibility ? document[property] : undefined;
        }
    }
    updateState();

    $(/blur$/.test(eventName) ? window : document).on(eventName, function(event) {
        var type = event.type;
        var originalEvent = event.originalEvent;

        // Avoid errors from triggered native events for which `originalEvent` is
        // not available.
        if (!originalEvent) {
            return;
        }

        var toElement = originalEvent.toElement;

        // If it’s a `{focusin,focusout}` event (IE), `fromElement` and `toElement`
        // should both be `null` or `undefined`; else, the page visibility hasn’t
        // changed, but the user just clicked somewhere in the doc. In IE9, we need
        // to check the `relatedTarget` property instead.
        if (
            !/^focus./.test(type) || (
                toElement === undefined &&
                originalEvent.fromElement === undefined &&
                originalEvent.relatedTarget === undefined
            )
        ) {
            $(document).triggerHandler(
                    property && document[property] || /^(?:blur|focusout)$/.test(type) ?
                        'hide' :
                        'show'
            );
        }
        // and update the current state
        updateState();
    });
}));