Using layer file to apply symbology to shapefile with ArcPy?

Question

I have code that doesn't work at the moment:

# Import arcpy module
import arcpy
# Script arguments
Input = arcpy.GetParameterAsText(0)
if Input == '#' or not Input:
 Input = "frame" # provide a default value if unspecified
Symbology = arcpy.GetParameterAsText(1)
if Symbology == '#' or not Symbology:
 Symbology = "symbology" # provide a default value if unspecified
### Local variables:
Rearrange = Symbology
line_connection_shp = Rearrange
### Process: Apply Symbology From Layer
arcpy.ApplySymbologyFromLayer_management(Input, Symbology)
Process: Points To Line
arcpy.PointsToLine_management(Rearrange, line_connection_shp, "MMSI", "", "NO_CLOSE")

What this is doing is applying my layer symbology (a .lyr file) to a shapefile.

This results in an error:

ERROR 000732: Input Layer: Dataset C:\temp\test.shp does not exist or is not supported.

It works fine when I apply these tools myself, but creates errors while using it in Python.

This must be an issue with trying to input a shapefile into the ApplyFromSymbology tool, so is there a way to use a shapefile with that tool?

Answer 1

You are not providing the code required to add a layer to the map at all.

You need a feature layer from the shapefile and then save it on disk as the .lyr file.

inputLocationsSavedFcFeatLyr = arcpy.MakeFeatureLayer_management(input_locations_fc,"Stops")
arcpy.SaveToLayerFile_management(in_layer=inputLocationsSavedFcFeatLyr,
 out_layer=r"C:\GIS\LocationPoints1.lyr",
 is_relative_path=None,version=None)

Specify the template layer (with symbology you want to be applied) + apply it:

locationsTemplate_layer = mp.Layer(r"C:\GIS\LocationPoints1.lyr")
arcpy.ApplySymbologyFromLayer_management(locationsTemplate_layer,r"C:\GIS\LocationPointsTemplate.lyr")

Now you can add the .lyr file to the map document (here, it is added to a group layer):

mp.AddLayerToGroup(df, targetGroupLayer, locationsTemplate_layer)

More help docs on that is here:

• Layer (arcpy.mapping)
• AddLayer (arcpy.mapping)