Update the modification status in the mode bar.

        This slot is Connected to the ``modificationChanged`` signal
        from the ``QtmacsScintilla`` widget.

def qteModificationChanged(self, mod):
        """
        Update the modification status in the mode bar.

        This slot is Connected to the ``modificationChanged`` signal
        from the ``QtmacsScintilla`` widget.
        """
        if mod:
            s = '*'
        else:
            s = '-'
        self._qteModeBar.qteChangeModeValue('MODIFIED', s)