topic Python addin error: SystemError: NULL object passed to Py_BuildValue in Python Questions

Python addin error: SystemError: NULL object passed to Py_BuildValue

ionarawilson1 — Tue, 29 Oct 2013 14:39:17 GMT

I have a python addin combox. Based on the selection of the combobox the user will get a message. When I test it inside Arcmap, I can see an error in the python window. Can anybody tell me what's wrong with my code that is producing this error? Thanks

This is the error:

SystemError: NULL object passed to Py_BuildValue

import arcpy
import pythonaddins

class ComboBoxClass1(object):
    """Implementation for SARS6_addin.combobox (ComboBox)"""
    def __init__(self):
        self.items = ["Forestry Stewardship", "Forestry Management Plan", "Reforestation Accomplished - TFS", "Reforestation Accomplished - Non TFS", "Tree Farm Program - Reinspections", "Tree Farm Program - New Inspections", "Certified Forest Steward - Assist", "Timber Theft Damage Appraisal", "Referral - Consulting Forester", "Referral Vendor", "Incidental Rural Forestry", "Prevention and Reduction of Pest Losses", "Forest Health Monitoring - Survey", "Forest Inventory & Analysis (FIA) Assist", "Best Management Practices (BMP) Assist"]
        self.editable = False
        self.enabled = True
        self.dropdownWidth = 'WWWWWWWWWWWWWWWWWWWWWWWWWWWWW'
        self.width = 'WWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWW'
    def onSelChange(self, selection):
         if selection == "Forestry Stewardship":
                    pythonaddins.MessageBox("If in edit mode, please digitize the stewardship boundary and run the ""Stewardship"" tool", "Warning", 0)
    def onEditChange(self, text):
        pass
    def onFocus(self, focused):
        pass
    def onEnter(self):
        pass
    def refresh(self):
        pass

Re: Python addin error: SystemError: NULL object passed to Py_BuildValue

JasonScheirer — Tue, 29 Oct 2013 14:52:31 GMT

When does this occur? In what method? Does it give any more information? Do the items you assign in __init__ show up in the combobox? What version of ArcGIS are you using?

Re: Python addin error: SystemError: NULL object passed to Py_BuildValue

ionarawilson1 — Tue, 29 Oct 2013 14:56:07 GMT

It shows up after I hit ok in the message box. The items appear, but after I click ok, the item does not stay selected. I can see the item and the other items if I use the dropdown menu, but it would be nice if it stayed selected. It does not provide any other information. I am using 10.1. Thank you Jason!

Re: Python addin error: SystemError: NULL object passed to Py_BuildValue

JasonScheirer — Tue, 29 Oct 2013 15:06:27 GMT

Issue appears to have been fixed either in 10.1 SP1 or 10.2.

Re: Python addin error: SystemError: NULL object passed to Py_BuildValue

ionarawilson1 — Tue, 29 Oct 2013 15:09:46 GMT

I do have sp1

Re: Python addin error: SystemError: NULL object passed to Py_BuildValue

ionarawilson1 — Tue, 29 Oct 2013 15:10:55 GMT

How can I make it stay selected after I hit ok? thanks

Re: Python addin error: SystemError: NULL object passed to Py_BuildValue

ionarawilson1 — Tue, 29 Oct 2013 18:57:49 GMT

I figured: You just need to make it editable