On Scroll Ending trigger in StackedCards acts to late


I am facing a problem when I use the OnScrollEnding trigger in a StackedCards mobile app. 

When both the fields MaxRecords and IncrementRecords are set to 10, it is possible to swipe 10 times. After that, the screen will be blank. 

Swiping the eleventh time, the trigger starts the OnScrollEnding client action (my action starts with an INFO-notification), but the screen remains blank. 

After some more swipes, data of more records is shown by each other in one screen.

Setting the Animate Items of the list group to true does not have any effect.



Outsystems Mobile Apps (PlanetHopper)

Can you share your OML?

Hi Andrew,

See my file attached.

Regards, René Cornet


Hi Rene,

You're correct.  The OnScrollEnding action that's attached to the List in the StackedCards wasn't meant to be used with the StackedCards.

First, congrats on working you're way through the 2 hour course on 11.  It was built for 10 and we're working on an update for 11 that removes the need for starting with the template and all the dependencies.

OnScrollEnding gets activated for real lists when scrolling is detected and the scroll approaches the MaxRecords.  The action and the GUI are linked in the generated code so that we get a smooth continuous scroll even though we've only loaded a few records to start.  We originally used the default MaxRecords of 20, but since there are only 20 planets, it wasn't being used anyway.  It got updated to 10 and the data refresh doesn't sync with the cards correctly.

We could try to implement this in the StackedCards by using the general logic of OnScrollEnding but placing it in the OnSwipes that are moving us forward through the list.  We would want to refresh the data before we get to the MaxRecord so that the list has the 11 record to display and doesn't come back blank the way it currently does.

Does that make sense?  Not sure the explanation is clear enough.




Hi Scott,

Thanks for the explanation. I will wait for the eleventh version.