Bug: Gallery inside datacard inside form with delegable datasource - skipping first 100 matches

[PaulD1]

I think the latest update to studio is the cause of this bug which appears to affect both Studio and the web player (have not tested on the iOS or Android players).

Looking at an App for a client that has a gallery inside a Datacard inside a Form and is populate by a delegable filter (SQL datasource, using Search based on the text entered in a text box) - we were not seeing the expected results (missing entries we would expect to see). A copy of the Gallery - identical in every way but outside the Form works as expected.

A few hours of research and found (by checking Monitor) that when the Gallery is in the Datacard, PowerApps does the usual 'Get Top 100 rows' but then immediately (without any interaction by the user) performs a second data-fetch using (Skip 100 Rows, Get 100 Rows). The results of the first data-fetch don't show up in the Gallery.

We recreated several galleries to confirm this behaviour.

The client will log a ticket with MS Support. Adding to this post to warn the community.

I know I am a broken record on PowerApps releases and (the lack of) quality control) but I'll say it yet again - this platform is pretty much unusable for any kind of serious or critical App. Any cost savings made by the faster development times of drag-n-drop, low-code development is soon lost on maintenance trying to fix issues that often turn out to be yet more platform issues introduced by the latest weekly update ☹️

[v-qiaqi-msft]

Hi@PaulD1,

Thanks for your sharing.

I have a test on my side and the situation is confirmed on my side.

Inserting a Gallery into a data card is not allowed while the users could copy and paste it to the data card. This should be a bug. 

If possible, please post the updates when there is some progress.

Best Regards,

Qi

[PaulD1]

The inability to copy/paste reliably is indeed a UI bug, thanks for checking that.

The specific issue affecting us at the moment though is that a gallery inside a form's datacard is behaving differently to a gallery with the same properties outside of the data card.

The gallery in the datacard has as it's items property a delegable formula incorporating Search (though other predicates appear to cause the same issue) - when entering a value in the text box on which forms part of the Search, a 'Get Rows' is fired (specifying top 100) and then immediately (tenths of a second) another 'Get Rows' is performed but specifying 'skip 100'. The gallery fills with the second batch of 100 rows, the first batch seemingly being discarded.

[PaulD1 · Accepted solution]

Heard back from Support. Adding a gallery to a datacard apparently is not an expected/supported scenario and the difficulty in adding galleries to Datacards apparently is a conscious choice to discourage users from attempting to do this - though it is possible to do it if you try. It would be nice if there was a message rather than this just appear to be another a UI bug!

If you have followed this 'model' (Gallery with delegable datasource inside a Datacard) then the recommendation is to use a Behaviour action to populate a collection and then use the collection as the datasource for the gallery.