Question

 window.popup = window.open($(this).attr('href'), 'Ad', 'left=20,top=20,width=500,height=500,toolbar=1,resizable=0');
 $(window.popup).onload = function()
        {
                alert("Popup has loaded a page");
        };

This doesn’t work in any browser I’ve tried it with (IE, Firefox, Chrome). How can I detect when a page is loaded in the window (like an iframe onload)?

Answer 1

If the pop-up’s document is from a different domain, this is simply not possible.

Update April 2015: I was wrong about this: if you own both domains, you can use window.postMessage and the message event in pretty much all browsers that are relevant today.

If not, there’s still no way you’ll be able to make this work cross-browser without some help from the document being loaded into the pop-up. You need to be able to detect a change in the pop-up that occurs once it has loaded, which could be a variable that JavaScript in the pop-up page sets when it handles its own load event, or if you have some control of it you could add a call to a function in the opener.