How to I get Grid row info from ANOTHER JS routine?

I admit to being a little less than expert with JS and AW. I am writing a JavaScript routine for a button and want -- from that button's click --to reference an existing AW grid and find grab the data from the select row.

How do I do that? (I realize this is probably extremely newbie and I spent the last 1/2 hour trying to find an old post to explain this to me, but I couldn't). Everything starts with obj.xxxx but how do I get that object to begin with?

-- John Kiernan

You can use any javascript variable to keep reference to the grid or button objects -

var grid = new AW.UI.Grid;
var button = new AW.UI.Button;