Question

Suppose we have a website in which you click on a button, and that opens a popup (child) window using JavaScript. So let’s call the parent A and the popup P. In the source of A, we’d see something like this:

<script type="text/javascript">
P = window.open('P.html', 'P');
</script>

So as long as A is open, we can interact with P in JavaScript using the P variable. However, when I click on a link in A to go to B.html, I lose all the variables. Yet my popup window is still open, so I wonder if there’s any way I can link the two back together. Is there any way I can manipulate P from within B? Thanks much.

Answer 1

Well I figured out that, to my pleasant surprise, the answer is YES. Mohammad’s solution of using window.top was not correct; when I try to access window.top from within P, that just returns a reference to P itself. RobG’s answer just kind of missed the point.

I found that if I do this periodically from within P, everything works:

<!-- A.html, B.html -->
<script type="text/javascript">
function setP(ref)
{
    P = ref;
}
</script>

<!-- P.html -->
<script type="text/javascript">
function updateParent()
{
    if ( typeof window.opener.setP == 'function' ) {
        window.opener.setP(window);
    }
}
window.setInterval(updateParent, 2000);
</script>

This way, even when I navigate the parent window from A to B, B will still be updated with a window reference to P and once that’s established the two windows can then communicate freely with each other again.