Making grid cells clickable in PHP

I've seen numerous messages in this forum that explain how to add functionality so that events can be fired off when a user clicks on items in the grid. The problem I have is that I'm working in PHP and I don't see how to implement the suggestions in my code.

For example, one suggestion is to add the following:
obj.setAction("click", function(src){document.location.href = src.getProperty("item/text")});

My question is: where does that statement need to go? Does it go in my php page that actually displays the grid or does it have to go in another page (e.g., activewidgets.php, grid.js)?

Thanks!