Sets the gtk.list_item_factory.ListItemFactory to use for populating the gtk.list_header.ListHeader objects used in section headers.
If this factory is set to null, the list will not show section headers.
the factory to use
Sets the gtk.list_item_factory.ListItemFactory to use for populating the gtk.list_header.ListHeader objects used in section headers.
If this factory is set to null, the list will not show section headers.