Citizen Service Request modification

Dan Giersz

February 24, 2016 20:42

Using GE 4.4.2 and GVH 2.5.2

 

I am trying to limit the geographic location of where users can place the service request in this demo.  I tried adding a QueryTask that spatially queries our service area against the added point and then there is a Decision to see if the QueryTask returned any results. I tried using <featuresetname>.Features.Count > 0 in the Decision but it throws an error: Unhandled exception: 'Object reference not set to an instance of an object.' in activity '1.158: VisualBasicValue<Boolean>'. Object reference not set to an instance of an object.

 

Even if I just limit the QueryTask to where "1=1" and leave out the spatial filter.

 

And when I try to add an Alert with the string "<featuresetname>.Features.Count.toString I also get an error.

 

Workflow Designer shows no errors, but i am starting to think <featuresetname>.Features.Count can't be used. The Citizen Request Demo is pretty old, as is the Mailing list sample that does exactly what I am trying to do...

 

Any ideas?

 

 

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  Permanently deleted user

  February 24, 2016 21:25

  Hi Dan, 

   

  The error that you are getting means nothing has been assigned to one of the variables that you are using, most likely the feature set variable name. I was able to replicate the same error message on my end and it happened when I created a feature set variable, did not assign it anything and passed it to the "Decision" activity. I would double check to make sure you are referencing the correct feature set name and go from there.

   

  I hope this helps.

   

  Carmen

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  Dan Giersz

  February 24, 2016 21:57

  Thanks for the quick reply, Carmen!

   

  After your advice (and a nice long break) I went back through everything.  What it turned out being was the QueryTask was set to return IDs only.  I figured that was all I needed to make sure there was a feature at the location.  Simply setting it back to false was all it took to get everything working (even with the output fields of the QueryTask set to "OBJECTID").

   

   

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  Permanently deleted user

  March 02, 2017 23:06

  Hi Dan and Carmen, I  believe I am running into the exact same issue with my workflow. I am trying to search intersections and am getting the error "Unhandled exception: 'Value cannot be null. Parameter name: source' in activity '1.129: VisualBasicValue<Boolean>'. Value cannot be null." which I believe is coming from the Decision activity because nothing is getting passed from the Query task...if either of you would mind taking a look at my workflow it'd be greatly appreciated!

   

  https://drive.google.com/file/d/0B5rgPuFOw9yfblZIQ2ExMTVMdTA/view?usp=sharing

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  Amanda Frech

  April 20, 2017 18:36

  Hi Lisa,

   

  I believe you've been in contact with us for this one, but just in case any other users end up reading this topic, this one is indeed an issue from the QueryMap sequence in the workflow.  If the geocode activity doesn't generate any result (as opposed to completing properly and finding 0 matches) you'll see an error like this when you try to use addressCandidatesCollection.Count

   

  Amanda

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