void UpdateCellNumber()
{
if (aux > 0)
{//Si hay que actualizar el nº de la celda
selectedCell.setNum(aux);
//selectedCell.grid.Background = Brushes.Thistle;
selectedCell.Solved = true;
aux = -1;
}
else if (!selectedCell.Fixed && !selectedCell.Solved)
{
selectedCell.ShowPossibles();
}
//Marca como seleccionada
Unselect();
selectedCell.selected = true;
selectedCell.SelectionChanged();
}