def setupQuery(self, query, op, editor):
        """
        Returns the value from the editor.
        
        :param      op       | <str>
                    editor   | <QWidget> || None
        
        :return     <bool> | success
        """
        try:
            registry = self._operatorMap[nativestring(op)]
        except KeyError:
            return False
        
        op = registry.op
        value = registry.defaultValue
        
        if op is None:
            return False
        
        if editor is not None:
            value = self.editorValue(editor)
        
        query.setOperatorType(op)
        query.setValue(value)
        return True