changing the content of a model/view/store at run time

[pcr <pcr pcrt us>]

I'm trying to learn how to iterate over model rows in a manner similar to the code segment in section 9.3 of the gnome gtkmm tutorial.  Consider me a newbie; the "something" I want to do below is delete/clear/erase a row - really all rows so I can display a new set of rows in response to a user action like changing a radio button.  But I haven't been able to do it. Here is the snippit from section 9.3:

typedef Gtk::TreeModel::Children type_children; //minimise code length.
type_children children = refModel->children();
for(type_children::iterator iter = children.begin();
    iter != children.end(); ++iter)
{
  Gtk::TreeModel::Row row = *iter;
  //Do something with the row - see above for set/get.
}

I'm also confused by the following comment I found on line; I don't see how this can work with the above code either. 

iterator Gtk::TreeStore:erase(const iterator& iter)
	Returns an iterator to the next row or end() if there is none"

I hope you can help me .  Thanks, PCR