Slot for when the current index changes.
        Emits the :data:`AbstractLevel.new_root` signal.

        :param index: the new current index
        :type index: int
        :returns: None
        :rtype: None
        :raises: None

def current_changed(self, i):
        """Slot for when the current index changes.
        Emits the :data:`AbstractLevel.new_root` signal.

        :param index: the new current index
        :type index: int
        :returns: None
        :rtype: None
        :raises: None
        """
        m = self.model()
        ri = self.rootModelIndex()
        index = m.index(i, 0, ri)
        self.new_root.emit(index)