topic Re: How to not use a list item more than once. in ArcGIS Survey123 Questions

How to not use a list item more than once.

DougBrowning — Wed, 27 Feb 2019 15:32:24 GMT

I have a select one list in a repeat where I want to stop, or warn, a user if they pick an item more than once during the repeats. This list is about 1,300 items.

I created a field that keeps a running list from my repeat

join(", ", ${SpeciesList})

I tried this constraint on the list not(contains(${AllPlants}, ${SpeciesList})) but it always triggers since it is in the list as soon as i pick it.

Is there a way to count the number of string occurrences? Or remove it from the check somehow.

Thanks for any ideas

Re: How to not use a list item more than once.

DougBrowning — Mon, 04 Mar 2019 22:01:18 GMT

I got this to kinda work but it has issues. What I do is take off the last 3 chars of the running list, thus breaking up that last value - which is then not found.

not(contains(substr(${AllPlants}, 0, string-length(${AllPlants}) - 3), ${SpeciesList}))

If you go down the repeat in order this works. But this falls apart if you go backwards in a repeat and try and change a value.

What would be nice is a count of the number of substrings found. so substr("XXXXX", "X") returns 5 not just true false. Or a contains that returns the position the string was found would work also.

Thanks for any ideas.

Re: How to not use a list item more than once.

EvanR — Thu, 04 Feb 2021 22:55:48 GMT

Trying to implement your solution because I had problems with the JavaScript function. However, the question I'm trying to add this constraint to is a decimal type, which is causing issues. I eventually figured out how to calculate a version of my list of entries with the current entry removed (non-trivial). However, because Survey123 lists appear to be a string type at their core rather than a true list, any subsequent value that matches part of a previous entry will not be allowed. For example, if my list of entries is "1,1.5,3" and I try to enter 5, it won't allow it since 1.5 contains a 5. Any suggestions? All entries will be positive values that are divisible by 0.5.

For reference, here's the complicated formula I came up with that calculates a version of the entries list with the current entry removed: if(string-length(${InterceptList})=string-length(string(${PointDistance_m})),"",substr(${InterceptList},0,string-length(${InterceptList})-string-length(string(${PointDistance_m}))))

${InterceptList} is the raw list and ${PointDistance_m} is the question I'm trying to constrain. Have to coerce values to string, and the if statement was necessary because any time I was making an initial entry it would appear in the list (removal of the current entry only seemed to work for entries after the first).

Re: How to not use a list item more than once.

EvanR — Mon, 08 Feb 2021 14:44:04 GMT

Think I may have solved it: I calculated a second version of the value in question by multiplying each entry by a constant and use THAT for the list and the duplicate check. I haven't yet tested it fully but it seems to work so far. First tried adding a constant, but that caused problems as well (e.g., if you add 0.3, 200, etc. to 16.5 and to 6.5 the latter will still be a substring of the former).

Re: How to not use a list item more than once.

AndrewPadilla — Wed, 03 Mar 2021 23:18:26 GMT

I am looking for this solution as well. I attempted to use JavaScript as described in

JavaScript funtions in Survey123 (https://community.esri.com/t5/arcgis-survey123-blog/extending-survey123-smart-forms-with-custom-js-functions/ba-p/898782) but was unable to reproduce a working HasDups function in Survey123. Has anyone else been able to successfully reproduce this example? The constraint does not seem to register correctly. In the example below any fruits entered are an invalid selection with the constraint (${dups}=false).

I attached an example file and script:

function HasDups (myArray){

return new Set(myArray).size !== myArray.length;

}

Thanks,

Andy

Re: How to not use a list item more than once.

EvanR — Thu, 04 Mar 2021 13:13:46 GMT

Did you download repeats.js and place it in an "extensions" directory within your survey directory? You have to do that before you can call the script from your XLSForm. I was able to get it to work in Survey123 Connect once I figured out that step, but it didn't work when deployed to field tablets because of some restrictions on what exact flavors of AGOL etc. allow JavaScript, which was a bummer.

See here and also here. Let me know if that doesn't work for you and I'll take a closer look.

Re: How to not use a list item more than once.

AndrewPadilla — Thu, 04 Mar 2021 18:50:24 GMT

Thanks for your response @EvanR. Yes, I should have mentioned, I had placed 'myFunctions.js' in a scripts folder (I believe the extensions folder works the same). In the end I did get it to work. It was as simple as placing quotation marks around false in my constraint. I have attached a revised working example. JavaScript files cannot be added here. One would need to create a 'myFunctions.js' and use the following function and place it in a scripts folder with in the survey folder:

function HasDups (myArray){

return new Set(myArray).size !== myArray.length;

}

Re: How to not use a list item more than once.

AndreaBaquerizo — Sun, 27 Jun 2021 18:33:04 GMT

Hi @AndrewPadilla ,

I have tried to use the javascript code in a ' myFunctions.js'

function HasDups (myArray){

return new Set(myArray).size !== myArray.length;

}

but I have a error in the script called "Expected token ;" If you know what the error is, could you tell me a solution

Thanks

Re: How to not use a list item more than once.

AndrewPadilla — Mon, 28 Jun 2021 17:24:54 GMT

Hi @AndreaBaquerizo,

I am not an expert in writing JavaScript but it looks like you have the formula correct as pasted above but the screen shot you attached does not match. You need to remove the space between "(myArray)" and ".size", and also add a space between ".size" and "!" (see attachment). Easiest way would be to copy and paste the original formula. I attached a screen shot of my .js file. I hope that helps.

Re: How to not use a list item more than once.

ChrisRoberts2 — Fri, 02 Jul 2021 00:42:36 GMT

The JS fuction works great it my dev version of my survey, but as the production version will be a public survey I just realised its not going to work! Is there another way to achieve the same result? Within the repeat the user has a list of 12 target speices to survey and count, I dont wan them counting the same species twice as a seperate record.

Cheers

Chris

Re: How to not use a list item more than once.

CSR_GarinHirata — Wed, 08 Dec 2021 20:33:48 GMT

@DougBrowning I had a question about your way of checking for duplicates. Does it work in the Survey123 Web app? I have something working in the mobile app version, but it doesn't work in the web app survey. I am not using a javascript file. Any Thoughts? Thanks!

Re: How to not use a list item more than once.

DougBrowning — Wed, 08 Dec 2021 20:51:36 GMT

I would think it would work. I do not use the web much. One common gottcha in the web is + does not work to combine strings. You have to use concat(). Best thing is to post the form.

Re: How to not use a list item more than once.

CSR_GarinHirata — Wed, 08 Dec 2021 20:58:18 GMT

I highlighted the repeat section in the excel spreadsheet. Thanks for taking a look.

Re: How to not use a list item more than once.

DougBrowning — Wed, 08 Dec 2021 23:29:05 GMT

I see it works in Connect fine

Sorry I have no idea on the web. I do not see anything but I never use the web forms so I really do not know. Maybe someone else will. Sorry

Oh wait I see you are using reserved words. These little green boxes mean not cool. Could be it.

Also not sure you can start a field with a special char. Prob not

_size

Hope that does it

Re: How to not use a list item more than once.

CSR_GarinHirata — Wed, 08 Dec 2021 23:50:09 GMT

I made some of those changes, but with no luck. Thanks for all your help. I might have to make a call into esri support to see what might be wrong.

Thanks again,

Re: How to not use a list item more than once.

DougBrowning — Thu, 09 Dec 2021 00:29:36 GMT

Did you publish it as a all new layer? If not those fields would still be in the service and could still cause issues. Its worth a shot.

Re: How to not use a list item more than once.

CSR_GarinHirata — Thu, 09 Dec 2021 21:22:07 GMT

I tried with no success. I ran it by esri. So we'll see what they find out.

Re: How to not use a list item more than once.

NourSalam — Fri, 08 Apr 2022 18:43:09 GMT

I have used this workaround for a very similar use case and found it very useful! I do hope the count of duplicates becomes possible at some point!

Re: How to not use a list item more than once.

DougBrowning — Fri, 15 Apr 2022 16:26:03 GMT

I’ve been mean to update this there’s been a couple new issues come up in the new three. 3.14 engine. I did get it working but it’s a little funky I’ll have to come back and post it I’m in the field now. Basically you have to use once around the join so that you can go backwards. Then on your check add a comma in there on the check then it won’t find partial strings. And then the real funky one is join works differently on the very first element see you got a run a check for that. ifI don’t post this next week remind me.

Re: How to not use a list item more than once.

RobertGeitner — Wed, 22 Feb 2023 15:27:52 GMT

I am also interested in not only counting unique selections across repeats, but also then using the returned selections to calculate a value. Has there been any advance in this in the last 14 months?