Programmatically adding .shp file to .mxd file

Question

I have spent hours attempting to find the solution to the following problem online, but all answers I have found are quite old, and none work. Here is the situation: I have a variety of .shp files. I have a blank mxd file. I want to add the .shp files into the .mxd file.

Various stackoverflow and stackexchange answers would have me believe that the answer to my problem lies in either: arcpy.MakeFeatureLayer_management(,) or arcpy.mapping.Layer()

Unfortunately, I get a similar error no matter what approach I take.

The exact code from my most recent attempt (I'm really not sure how this could possibly be simpler):

import arcpy
arcpy.env.workspace = "C:/test"
arcpy.Exists("shapefile.shp") #returns True
arcpy.mapping.Layer("shapefile.shp")

It is at this point that I receive the following error: Traceback (most recent call last): ... File "C:\Program Files\ArcGIS\Server\arcpy\arcpy\arcobjects\mixins.py", line 289 in init super(LayerMixin, self).init(lyrfile) File "C:\Program Files\ArcGIS\Server\arcpy\arcpy\arcobjects_base.py", line 47, in init for arg in args ValueError: Object: CreateObject Layer invalid data source

Edit: exact code from my attempt using the other function

import arcpy
arcpy.env.workspace = "C:/test"
arcpy.Exists("shapefile.shp") #returns True
arcpy.MakeFeatureLayer_management("shapefile.shp","myshapelayer")

In this case, I receive the following error: Traceback (most recent call last): ... arcgisscripting.ExecuteError: ERROR 000229: Cannot open shapefile.shp Failed to execute .

Can anyone advise me as to how to proceed? I have found almost five different solutions suggesting that this is the procedure which I should follow, but it definitely isn't working for me. I am using Python 2.7.

Additional Notes: -I have manually loaded the shapefile in ArcMap, it loads and displays correctly.

Answer 1

You're improperly using the arcpy.mapping.Layer function.

arcpy.mapping.Layer takes a Layer File (*.lyr) saved on disk and returns a Layer Object from that.

Layer Objects have methods which you can use to change various properties of the layer, such as its visibility, transparency, definition query, etc.

You're giving it a shapefile. Hence the error, invalid data source.

Just use the MakeFeatureLayer_management function which will create an in_memory Feature Layer and automatically add it to the current MXD, where the first argument is the absolute path to your shapefile, and the second argument is a string representing the name of the layer as it will appear in the Table of Contents.

arcpy.MakeFeatureLayer_management(r"C:\SomeDataPath\shapefile.shp", "MyShapefile")

Answer 2

The following code contains more than you need, but it will show that you need to specify or create a blank mxd, then specify a data frame, then activate that data frame then add your layers/shapefiles with optional symbology specified

'''
mxd_create.py

Author:   Dan.Patterson@carleton.ca
Purpose:  create a base mxd and populate it with default values
Requires: specify the files to load and the default dataframes etc
template paths
ie
C:\Program Files (x86)\ArcGIS\Desktop10.2\MapTemplates\Traditional Layouts\LetterLandscape.mxd
C:\Program Files (x86)\ArcGIS\Desktop10.2\MapTemplates\Traditional Layouts\LetterPortrait.mxd
'''    
import arcpy
import sys
import os
import shutil

script = sys.argv[0]  # script name and location
mxd_src = "C:/!test/mapping/mxd_test02.mxd"  # a shell empty project
path, doc = os.path.split(mxd_src)
template = path + "/LetterPortrait.mxd"
shutil.copyfile(template,doc)

arcpy.env.workspace = path + "/shapefiles"
arcpy.overwriteOutputs = True

shp_files = ["AOI_mtm9.shp", "RandomPnts.shp"]
lyr_files = ["AOI_mtm9.lyr","RandomPnts.lyr"]
arcpy.ListFiles("*.lyr")    #use this to check above

author = "This could be you!!!!"
description = "Demo project working with the arcpy.mapping module and Python"
title = "Arcpy Mapping Demo:  Introduction to arcpy.mapping and Python interaction"
mxd = arcpy.mapping.MapDocument(doc)
mxd.author = author
mxd.description = description
mxd.title = title
mxd.relativePaths = True

df = arcpy.mapping.ListDataFrames(mxd)[0]   # list of data frames, 1 exists by default
df.name = "Sample files"                    # set its title
mxd.activeView = df.name                    # activate it

for shp in shp_files:                       # cycle through the list of shapefiles
  #fn, ext = os.path.splitext(f)            # for testing
  lyr = arcpy.mapping.Layer(shp)            # add the files and auto arrange
  arcpy.mapping.AddLayer(df,lyr,"AUTO_ARRANGE")     
arcpy.ApplySymbologyFromLayer_management(lyr,lyr_files[1])  # apply symbology from lyr files
#arcpy.mapping.UpdateLayer(df, updateLayer, sourceLayer, True) 
arcpy.RefreshActiveView()
mxd.save()
del template, shp_files, lyr_files, lyr, df, mxd
os.startfile(doc)
del doc
##

Answer 3

I have finally solved the problem - it was actually a simple fix - a misunderstanding on my part. I failed to realize that a "shapefile" is far more than just the ".shp" file. Apparently you need to have all (five?) files (with all (five?) extensions) in the appropriate directory in order for the function to work properly. After adding my .dbfs, my .xmls, etc., it works just fine.