Issue with populating list box in chain app

Question

Hello,

I have two chained apps, App1 & App2. App1 takes user input, which is used to determine data that populates a list box in App2. App1 outputs this data into a yxdb file (UsrInput_BUNum.yxdb). App2 should show a list box with data from this .yxdb file and do some more calculations. The issue is the list box retains values from when App2 was run and doesn't dynamically capture latest data in the .yxdb file. When App1 is run for input value “99999999S”, it gives two values that populate listbox in App2 as shown in first image below. But when App1 is run for input value “77777777A”, it gives two new values which are not populating listbox in App2 as shown in second image.

Please see both apps & associated input/output files attached. Thanks for your help.

App1.yxwz

App2.yxwz

Example_BU_Nums.yxdb

UsrInput_BUNum.yxdb

Example BU Types.xlsx

AngelosPachis · Accepted Answer

Hi @SriKoka ,

The reason why those values don't appear correctly in your App2 listbox is that everything inside App2 will run once you click "Finish" in the second interface box but  you want your listbox to be updated when App1 finishes and before App2 starts.

So what's happening now is:

App1 starts > Show results from Browse tool > Listbox shows values from last successful run, independent from your App1 selections > App2 starts > Listbox values get updated > App 2 finishes

I found this post in the community that gives a very nice explanation of what's going on :

https://community.alteryx.com/t5/Alteryx-Designer-Discussions/List-Box-Input-not-updating-in-2nd-App-of-the-Chained-App/td-p/370231

What you have to do to solve it is in your App1, add a transpose tool and formula tool to create the output that will be fed to App2 and should have the following format

Then in your App 2, delete everything before your listbox and in your listbox tool, select to read from an external source and point it into the output file from App1

Your app should then run fine and be updated based on your selections.

Hope that helps, let me know if that worked for you.

Regards,

Angelos