JavaScript popup window with close event on button click

window.open() is a method to open a new browser window.

Javascript code to open window popup center aligned to page with close event on button click:

$(btn-container).on("click", function() {
    var w = 620;
    var h = 350;
    var win = window.open('http://achieveee.com', 'Achieveee', 'resizable,toolbar=0,location=0,scrollbars=1,menubar=0,width='+w+',height='+h+',top='+(screen.height-h)/2+',left='+(screen.width-w)/2+'');

    var timer = setInterval(function() {
        if (win.closed) {
            clearInterval(timer);
            alert('closed');
        }
    }, 1000);
});