How to move the focus

[DataBug]

I'm trying to move the focus from a form to a subform and can't quite figure out how to do it.

I have a calculated field on the main main form called ChkAmt which is the sum of a field called Amount in the subform.

What I want to happen is this :

After update of Amount, go to main form and requery ChkAmt then move the focus back to the subform.

I can do everything except get the focus back to the subform.

Also, is there any way to save a record using a macro ?

Thanks