def maxNotchSize( self, orientation ):
        """
        Returns the maximum size for this ruler based on its notches and the
        given orientation.
        
        :param      orientation | <Qt.Orientation>
        
        :return     <int>
        """
        metrics = QFontMetrics(QApplication.font())
        
        if orientation == Qt.Vertical:
            notch = ''
            for n in self.notches():
                if len(nativestring(n)) > len(nativestring(notch)):
                    notch = nativestring(n)
            
            return metrics.width(notch)
        else:
            return metrics.height()
Returns the maximum size for this ruler based on its notches and the
        given orientation.
        
        :param      orientation | <Qt.Orientation>
        
        :return     <int>