Select by location in ArcPy?

Question

i work with arcview 10.3 on 20 mxd's (each mxd has 25 layers) and i try to do select by location (with arcpy) and want to see a layers that are visible in the current map extent only. All Other layers that do not get in the current map extent i want to remove them from the data frame. I try this code:

import arcpy,os,sys,string
import arcpy.mapping
from arcpy import env

env.overwriteOutput = True  
env.workspace = r"C:\Project"
for mxdname in arcpy.ListFiles('*.mxd'):
     print mxdname
     print '----Removed lyr----'
     mxd = arcpy.mapping.MapDocument(r"C:\Project\\" + mxdname)
     df = arcpy.mapping.ListDataFrames(mxd, "Layers")[0]
     for lyr in arcpy.mapping.ListLayers(mxd, "" ,df):
         arcpy.MakeFeatureLayer_management(lyr.dataSource, "lyr")
         dfAsFeature = arcpy.Polygon(arcpy.Array([df.extent.lowerLeft,   df.extent.lowerRight, df.extent.upperRight, df.extent.upperLeft]),
                        df.spatialReference)
         arcpy.SelectLayerByLocation_management("lyr", "INTERSECT", dfAsFeature)

         if int(arcpy.GetCount_management("lyr").getOutput(0)) == 0:
              arcpy.mapping.RemoveLayer(df, lyr)
              print lyr

     mxd.save()
del mxd

i get an error when the layers are in Group layer:

>>> 
Project.mxd
----Removed lyr----

Traceback (most recent call last):
  File "C:\yaron\shonot\software\gis\tools\YARON_SCRIPTS\SelectLayerByLocation2.py",     line 22, in <module>
    arcpy.MakeFeatureLayer_management(lyr.dataSource, "lyr")
  File "C:\Program Files (x86)\ArcGIS\Desktop10.3\ArcPy\arcpy\arcobjects\_base.py", line 78, in _get
    (attr_name, self.__class__.__name__))
NameError: The attribute 'dataSource' is not supported on this instance of Layer.
>>>      

Answer 1

Ok, the first error is easy to avoid. It's failing because you are trying to find the datasource of a group layer, and group layers don't have data sources. Filter the group layers out by doing this:

for lyr in arcpy.mapping.ListLayers(mxd, "" ,df):
     if not lyr.supports("DATASOURCE"):
         continue
     #further code here for non-group layers

The supports() method is the best way to check for whether a given layer object has a certain property. Here's more info (scroll down to find the supports method).

Regarding the other issue, I assume that you are trying to avoid rasters (because you can't do a select by location on a raster layer). If this is the case, you can do a similar filter as above, using the isRasterLayer property:

for lyr in arcpy.mapping.ListLayers(mxd, "" ,df):
     if lyr.isRasterLayer:
         continue
     #further code here for non-raster layers

Ultimately, you should use the following to accomplish both of the above tasks:

for lyr in arcpy.mapping.ListLayers(mxd, "" ,df):
     if not lyr.isFeatureLayer:
         continue
     #further code here for only feature layers (no rasters, basemaps or group layers)

You also seem to have run into a problem with the MakeFeatureLayer operation. I believe that it's unnecessary anyway (because you're working with layer objects already). Try removing that line altogether and just referencing lyr instead of "lyr".