Change Symbol Size and Color for Multiple Feature Classes

Question

I need to expediently make an identical change to the symbol size and color of multiple feature classes. This can be done for layer transparency through a script such as:

mxd = arcpy.mapping.MapDocument("CURRENT")
for lyr in arcpy.mapping.ListLayers(mxd):
    if lyr.name == 'FC1' or 'FC2':
        if lyr.supports('TRANSPARENCY'):
            transparency = str(lyr.transparency)
            lyr.transparency = 45

But as far as I know, the color, size, and symbol type characteristics are not as easy to access and change. Any ideas on how this could be done?

Answer 1

It's true that you can't change color or symbol size for layers directly using arcpy. Instead you'd create a layer with the desired symbology and save it as a .lyr file.

You can then use Apply Symbology From Layer on the layer you wish to alter.