topic Re: setting blank " "output feature class value for Python toolbox parameter in Python Questions

setting blank " "output feature class value for Python toolbox parameter

DaveVerbyla — Wed, 01 Apr 2015 22:42:37 GMT

I am new to Python toolboxes. I have 2 parameters, param0 is an input text file, param1 is an output feature class.

I want param1 disabled,

which works fine, once it is enabled, I want it blank,

but it is populated with "C:\Users\Dave\Documents\ArcGIS\Default.gdb\test_CreatePolygon"

def updateParameters(self, parameters):

"""Modify the values and properties of parameters before internal

validation is performed. This method is called whenever a parameter

has been changed."""

if ( parameters[0].value):

parameters[1].enabled = True

parameters[1].value = ""

return

Re: setting blank " "output feature class value for Python toolbox parameter

AdamCox1 — Thu, 02 Apr 2015 22:54:12 GMT

You don't need the parentheses around the if condition... does removing those change the outcome?

Re: setting blank " "output feature class value for Python toolbox parameter

BlakeTerhune — Thu, 02 Apr 2015 23:41:01 GMT

I don't know if I follow exactly what you're getting at here, but I think you need to actually return something from your method; probably parameters. Right now your changing the .enabled and .value attributes of parameters[1], but those changes are only in the local variables for the method, they don't go anywhere. Try this at the end.

return parameters

Then I'm assuming you use parameters as input for some other process or method, in which case it should have the new properties you set in updateParameters().

Thank you, Adam Cox, for the clarification.

Re: setting blank " "output feature class value for Python toolbox parameter

AdamCox1 — Fri, 03 Apr 2015 14:41:24 GMT

No, see this documentation: ArcGIS Help 10.1 Go down to the examples and you'll see that, just like in the normal ToolValidator class for script tools (i.e. not in a Python toolbox), the updateParameters() method does not return any objects.

Re: setting blank " "output feature class value for Python toolbox parameter

BlakeTerhune — Fri, 03 Apr 2015 14:51:30 GMT

I didn't realize this is was something that Esri designed. Thanks for the clarification.