How to get Column index from template

Part of mi Code:
obj.setColumnTemplate(new My.Templates.Input, 0);
obj.setColumnTemplate(new My.Templates.Input, 1);
obj.setColumnTemplate(new My.Templates.Input, 2);

and i have to get Column index
i try this:
obj.getColumnProperty(index); nothing :(

other:
var model = obj.getTemplate("top");
alert(model.getColumnProperty("index"));
but same error:
undefined

Alex plx u there?
somebody answer this plz
thank you in advanced

this.element().parentNode.parentNode.parentNode.getColumnProperty("index");