How change color of lines at shapefiles with various ID's?

I have a shapefile with roads and I want all the road to have the same color except from some road with specific ID. I have tried the following but at the figure it is shown with different color the last loop:

      for i = 1:size(id2select,1)
        roadColors = ...
        makesymbolspec('Line',{'Road_ID', id2select(i), 'Color','r'},... 
                              {'Default','Color','b'});        
        mapshow(map,'SymbolSpec',roadColors);
      end
  end

I tried also using drawnow but this is animated and I need to be permanent.