topic How do I properly use UpdateLayer to change symbology for layer? in Python Questions

How do I properly use UpdateLayer to change symbology for layer?

Kevin_C — Sun, 12 Dec 2021 16:46:45 GMT

I am trying to change the symbology of a layer in a map document using arcpy. I have a reference layer I am using. Please see the following code:

mxd = arcpy.mapping.MapDocument("CURRENT")
df = arcpy.mapping.ListDataFrames(mxd)[0]
nuristanGeol = arcpy.mapping.Layer(r"C:\GeolAfghanProvince.gdb\Nuristan_geology")
afgGeol = arcpy.mapping.Layer(r"C:\afgeolmap.lyr")
arcpy.mapping.UpdateLayer(df, nuristanGeol, afgGeol)

This doesn't return anything or update the layers with new symbology. I also tried refreshing the view and TOC.

What am I doing wrong here?

Thanks!

Re: How do I properly use UpdateLayer to change symbology for layer?

JoshuaBixby — Fri, 08 Feb 2019 23:03:49 GMT

This doesn't return anything

Regarding the code not returning anything, you need to AddLayer—Help | ArcGIS Desktop after you create it. That may address your second issue to, but I don't have time to test.

Re: How do I properly use UpdateLayer to change symbology for layer?

RandyBurton — Fri, 08 Feb 2019 23:54:47 GMT

There is also: Apply Symbology From Layer

Re: How do I properly use UpdateLayer to change symbology for layer?

Kevin_C — Sat, 09 Feb 2019 01:20:22 GMT

That isn't just for arcpy within ArcGIS Pro, assuming that's different somehow? I'm using ArcMap.

Re: How do I properly use UpdateLayer to change symbology for layer?

RandyBurton — Sat, 09 Feb 2019 01:26:57 GMT

For Desktop 10.3-10.6 versions: Apply Symbology From Layer

Re: How do I properly use UpdateLayer to change symbology for layer?

Kevin_C — Sat, 09 Feb 2019 01:29:20 GMT

Thanks, I'll try that out when I get back to work. Although I'm still trying to figure out how I screwed up UpdateLayer.

Re: How do I properly use UpdateLayer to change symbology for layer?

Kevin_C — Wed, 13 Feb 2019 22:12:17 GMT

The issue was me trying to use arcpy.mapping.Layer() to define the nuristanGeol feature class which is the layer to be updated. I should've used arcpy.mapping.ListLayers(mxd) to point a variable at nuristanGeol. And then call this variable within UpdateLayer().