jQurey浏览器页卡切换 用于实时接口的长轮询

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    <meta charset="UTF-8">
    <title>Document</title>

    <script type="text/javascript" src="http://mat1.gtimg.com/www/js/jquery/jquery-1.11.1.min.js"></script>
    <script>

/***
   切换浏览器tab，判断当前tab是否活跃
***/

    (function(g, h, $, b) {
        var e, i, f = ‘onfocusin‘ in h && ‘hasFocus‘ in h ? ‘focusin focusout‘ : ‘focus blur‘,
            d = [‘‘, ‘moz‘, ‘ms‘, ‘o‘, ‘webkit‘],
            c = $.support,
            a = $.event;
        while ((i = e = d.pop()) != b) {
            i = (e ? e + ‘H‘ : ‘h‘) + ‘idden‘;
            if (c.pageVisibility = typeof h[i] == ‘boolean‘) {
                f = e + ‘visibilitychange‘;
                break
            }
        }
        $(/blur$/.test(f) ? g : h).bind(f,
            function(m) {
                var l = m.type,
                    j = m.originalEvent,

                    k = j.toElement;

                if (!/^focus./.test(l) || (k == b && j.fromElement == b && j.relatedTarget == b)) {
                    a.trigger((i && h[i] || /^(?:blur|focusout)$/.test(l) ? ‘hide‘ : ‘show‘) + ‘.visibility‘)
                }
            })
    }(this, document, jQuery));

    var o={}
    o.$tabFlag = true;
     /**  切换页卡 **/  

    var changeTab=function() {

        //var _this = this;
        //var o = this.options;
        console.log(333)
        $(document).bind({
            ‘show.visibility‘: function() { // 当前活跃
                o.$tabFlag = true;

                console.log(222)
            },

            ‘hide.visibility‘: function() { // 失去当前状态
                o.$tabFlag = false;
                console.log(11111)
            }
        });
    }
    
    changeTab();

    </script>


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