Page loading indicator

Hello

I have a page called ‘Mashup’ in my top nav bar which pulls a lot of RSS data from various feeds (including twitter, youtube), and therefore takes a while to load.

I am using some ready-made javascript in the mashup page php template file which indicates loading, before the rss feeds are displayed – code here: http://pastebin.com/f2eccd33b

This works well if the Mashup page is already cached in a browser. But on first click, sometimes it takes too long for the mashup page to initially display, before the loading indicator shows up within it.

Is it possible to use this type of javascript code, though it’s not called when the mashup page is landed on, but before. I know I can place the code in header.php, but this results in ‘page loading’ indicator for any page click. I would only want it to show when the mashup page is clicked.

So I would need something like this in the header file?
If mashup page is clicked -> execute javascript loading indicator
(any other page click wouldn’t invoke this javascript).

If this makes sense, what php code would I need?

thanks