Canvas App Phantom Error

[frsbdg]

I have been chasing down an error in my canvas app for hours and remain completely stumped. Here's the situation:

When I click on an item in my app, it runs a Power Automate Flow and navigates do a different screen. The first time I do this in the app, I get this error message:

It is not clear what value the app is trying to convert to a number, and I have reviewed all my variables and added default values to the OnStart property so none of them are blank. The crazy thing is that if I go back to the original screen and click the item again, the error message is not triggered. So there must be something that is blank initially to trigger the error the first time, but after that it isn't blank and the error doesn't occur. And I have no idea what that thing might be.

Stranger still, when I use the activity monitor to try and locate the error, I found this little nugget:

What the heck is that? Everything is null, so I have no idea what it is or where it is. But it's throwing an error and could be the gremlin in my app.

This error doesn't prevent the app from working, but I find it aesthetically unpleasant to tell my users that they can ignore it. I've reached the stage of "I'd piss on a spark plug if I thought it would do any good" and would appreciate any assistance this community can offer.

[timl]

Hi @frsbdg 

When you click on an item in your app for the first time, does it get as far as running the Power Automate Flow?

If so, it might be worth checking the Flow run history. That might give you some insight as to what Power Apps is passing to the Flow and might help possibly identify the blank value that isn't being converted to a number.

[frsbdg]

Yes, the Flow runs fine the first time. I pass the internal ID of the SharePoint list item to the Flow, which returns a delimited string containing the version history. I tried commenting out the Flow, and I still get the same error.

Another thing that is peculiar is that when I edit the app, the error appears right away, when I preview the app and click the object on a different screen. 

[frsbdg · Accepted solution]

I duplicated the screen and deleted the edit form, tested it, and did not get the error message. I re-inserted an edit form and am adding the data cards back, one at a time. So far, the error does has not re-appeared. I must have had a bad function on a data card that was causing the error, but there was no indication which card/function was the problem.