Is it possible to connect a web part to the page viewer webpart? My
problem is that I need to populate a treeview web part when the user
clicks a row in a datagrid on another web part. I have not been able to
wrap a treeview in the smartpart and have given up trying to get a
treeview to render in a web part.

Currently, when the user clicks the row, it passes an ID to another web
page, doing a window.open()... Is it posible to send the ID to the page
displayed in the page viewer web part and have it update?