docs: def setCurrentSchema( self, schema ):
          """
          Sets the index for this combobox to the inputed schema instance.
          
          :param      schema      <orb.TableSchema>
          
          :return     <bool> success
          """
          if ( not schema in self._schemas ):
              return False
          
          index = self._schemas.index(schema)
          self.setCurrentIndex(index)
          return True