docs: def setQuery( self, query ):
          """
          Assigns the query for this widget, loading the query builder tree with
          the pertinent information.
          
          :param      query | <Query> || <QueryCompound> || None
          """
          tree = self.uiQueryTREE
          tree.blockSignals(True)
          tree.setUpdatesEnabled(False)
          
          tree.clear()
          
          # assign a top level query item
          if ( Q.typecheck(query) and not query.isNull() ):
              XQueryItem(tree, query)
          
          # assign a top level query group
          elif ( QueryCompound.typecheck(query) and not query.isNull() ):
              op_name = QueryCompound.Op[query.operatorType()].lower()
              
              for i, sub_query in enumerate(query.queries()):
                  if ( i ):
                      XJoinItem(tree, op_name)
                  
                  XQueryItem(tree, sub_query)
              
          tree.resizeToContents()
          tree.setUpdatesEnabled(True)
          tree.blockSignals(False)