if tab fadeIn, redirect

I have a tab:

<div id=tab1> ... </div>

And I want to do, if tab1 fadeIn, then redirect.

How would I do it? I would imagine something likes this:

if $('#ta开发者_如何学运维b1').fadeIn(function(){
        window.location = "http://google.com"
});

If what you mean is if the tab is hidden go somewhere then this syntax could work:

if ($("#tab1").is(":hidden")) {
 window.location = "http://www.google.com/";
}