topic Re: Using script tool parameters to update a multiple choice list of values to select from based on a fields attributes? in Python Questions

Using script tool parameters to update a multiple choice list of values to select from based on a fields attributes?

RPGIS — Tue, 07 Sep 2021 20:03:34 GMT

Hi,

I was wondering if there was a way to set up the script tool parameters to update a multiple choice selection list based on a fields attribute values. I think I set it up correctly ( by all means correct me if it is wrong ) but it doesn't seem to be working accordingly. I might be missing something, but since I generally never mess with this, it is a bit foreign to me. Any help on this would be greatly appreciated.

class ToolValidator: # Class to add custom behavior and properties to the tool and tool parameters. def __init__(self): # set self.params for use in other function self.params = arcpy.GetParameterInfo() def initializeParameters(self): # Customize parameter properties. # This gets called when the tool is opened. return def updateParameters(self): # Modify parameter values and properties. # This gets called each time a parameter is modified, before # standard validation. if params[3].value: fcfields = [field.name for field in arcpy.ListFields(params[3].value) if field.name == params[4].valueAsText] attributevalues = [row for row in arcpy.da.SearchCursor(featureclass, fcfields)] self.params[5].filter.list = set(attributevalues) return def updateMessages(self): # Customize messages for the parameters. # This gets called after standard validation. return # def isLicensed(self): # # set tool isLicensed. # return True

Thanks

Re: Using script tool parameters to update a multiple choice list of values to select from based on a fields attributes?

Anonymous User — Tue, 07 Sep 2021 20:12:08 GMT

Try indexing your row in your list comp:

attributevalues = [row[0] for row in arcpy.da.SearchCursor(featureclass, fcfields)]

Re: Using script tool parameters to update a multiple choice list of values to select from based on a fields attributes?

nzjs — Tue, 07 Sep 2021 20:52:38 GMT

Looks like you might need to change params[] to self.params[] in a couple of places.

Re: Using script tool parameters to update a multiple choice list of values to select from based on a fields attributes?

RPGIS — Wed, 08 Sep 2021 12:35:51 GMT

So I tried both of your suggestions, but I am still not getting the multiple selection that I am looking for. Here is the updated script but I can't seem to figure out what I am missing.

Do I need to initialize a parameter first before using the update parameter? If this is all correct then any ideas on how to accomplish this. I have never tinkered with the tool validations before so this is all new territory for me.

class ToolValidator: # Class to add custom behavior and properties to the tool and tool parameters. def __init__(self): # set self.params for use in other function self.params = arcpy.GetParameterInfo() def initializeParameters(self): # Customize parameter properties. # This gets called when the tool is opened. return def updateParameters(self): # Modify parameter values and properties. # This gets called each time a parameter is modified, before # standard validation. if self.params[3].value: featureclass = self.params[3].value fcfields = [field.name for field in arcpy.ListFields(featureclass) if field.name == self.params[4].valueAsText] attributevalues = [row[0] for row in arcpy.da.SearchCursor(featureclass, fcfields)] self.params[5].filter.list = set(attributevalues) return def updateMessages(self): # Customize messages for the parameters. # This gets called after standard validation. return # def isLicensed(self): # # set tool isLicensed. # return True

Re: Using script tool parameters to update a multiple choice list of values to select from based on a fields attributes?

RPGIS — Wed, 08 Sep 2021 14:21:25 GMT

I figured out the issue. I wasn't sure why I didn't notice it before but the tool is working with the exception of the indexing error that I need to troubleshoot.

class ToolValidator: # Class to add custom behavior and properties to the tool and tool parameters. def __init__(self): # set self.params for use in other function self.params = arcpy.GetParameterInfo() def initializeParameters(self): # Customize parameter properties. # This gets called when the tool is opened. return def updateParameters(self): # Modify parameter values and properties. # This gets called each time a parameter is modified, before # standard validation. featureclass = self.params[2].value fieldname = self.params[3].value SubdivisionLayers = self.params[4].filter if featureclass: fcfields = [field.name for field in arcpy.ListFields(featureclass) if field.name == fieldname] attributevalues = [row[0] for row in arcpy.da.SearchCursor(featureclass, fcfields)] UniqueAttributes = set(attributevalues) SubdivisionLayers.list = [str(value) for value in UniqueAttributes] return def updateMessages(self): # Customize messages for the parameters. # This gets called after standard validation. return # def isLicensed(self): # # set tool isLicensed. # return True

The other issue is that it is passing the values with a ';' in between. I think I know a workaround but I will keep trying or create another post for any assistance.