JavaScript Callback function Problem
<p>Please see my code below:</p>

<pre><code>        var callback = function(popup_window) {
            popup_window.close();
           //some more codes here
        };
        var prepare = function(cb) {
            popup_window = window.open("my_url");
            this.cb(popup_window);
        };
        function refresh(){
            prepare(callback);
        };
</code></pre>

<p>How can I pass the <strong>popup_window</strong> variable to the callback function ?</p>
