code: def query( self ):
          
          # build a query if not searching all
          q        = Q()
          operator = 'and'
          
          for i in range(self.uiQueryTREE.topLevelItemCount()):
              item = self.uiQueryTREE.topLevelItem(i)
              
              if ( isinstance(item, XQueryItem) ):
                  if ( operator == 'and' ):
                      q &= item.query()
                  else:
                      q |= item.query()
              else:
                  operator = nativestring(item.text(0))
          return q
docs: Returns the query this widget is representing from the tree widget.
          
          :return     <Query> || <QueryCompound> || None