updating treeviews based on bindingnavigator

Hi,

I have a Bindingnavigator on a form indicating a row in a table. Based on that row I want to fill a treeview control.

I use a sub to fill the treeview, using a datasource that has a reference to a text box bound to the bindingnavigator.

The thing is I don´t know on which event I should put it. I´ve tried a few places and it seems that anything depending on the bindingnavigator produces an error on opening up the form.

I need to put the code so that when the form opens, the treeview fills up based on the row the form is showing, but when I move to the next item, the treeview needs to be filled again.

Any ideas?

Fuga.