Call controller action from GridView (solved)

I want to call a controller action whenever the user clicks on a gridview row.

I use selectionChanged in the gridview to call a javascript function.

What is the code (javascript/ajax/etc.) that should be in this function to call the controller action?

For those interested, there is a working example here:

http://www.yiiframework.com/wiki/323/dynamic-parent-and-child-cgridciew-on-single-view-using-ajax-to-update-child-gridview-via-controller-with-many_many-relation-after-row-in-parent-gridview-was-clicked/