 example by setting the access mode of the observers in the example (Note that we do this after the attachments for our example).

\code
// Set access modes. This must be done after we attached objects to these nodes.
nodeA->setAccessMode(Observer::ReadOnlyAccess);
nodeB->setAccessMode(Observer::LockedAccess);
\endcode

The resulting observer widget is shown below. It must be noted that the ColumnAccess item view column must be provided by the observer context:

\image html observer_widget_doc_tree_view_acc