ComboBox with fixed visible entries

Hi I am having a serious issue with a ComboBox with 50 entries. I am building a app for RPI using Raspbian 27-05-2020 release & XOJO 2019r3.1. When the entries of the combobox exceed more than can be seen without scrolling, I am unable to access those that are not visible beyond the screen as the scrollbars/scrollbuttons do not appear. Also mouse scrolling does not scroll the items.
This functionality works just fine in XOJO 2017r1.
I have tried GTK3 theming as mentioned in the thread, but that does not work. In fact in the very examples if you add more entries to the ComboBox the same can be observed.
Can any of you experts please help me…

If not, can i restrict the ComboBox to just 5 entries and then a scroll bar appear. This would be great. XOJO documentation shows how to do that for mac os. I need the same functionality for Linux. Any pointers I am willing to try out as I am stuck at the moment due to this issue.

Thanks Amit

Are-you using the ComboBox as a PopupMenu ?

you could replace the combobox with a button and a window with a list.

The GTK3 docs dont seem to indicate that you can say “make N rows visible”
https://developer.gnome.org/gtk3/stable/GtkComboBox.html

Dear Markus,
The popupmenu & ComboBox both exhibit the same behavior. Yes I could replace the combobox with a button and a list box. But this is a already built application. I have 57 screens most have a combobox or popupmenu. The porject works fine in 2017r1 just adding more functionality as the customer needs them now. We have moved on to later versions of XOJO for other platforms and hoped the same would work for RPI (Raspbian). It indeed does except for the mentioned issue. Its sad if we need to use the 2017r1 release just for this projects upkeep.

Dear Norman,
yes I have gone through that page earlier I could not find any function that could do that. So I was hoping there could be a XOJO fix to the above issue, where by I am unable to scroll beyond the limits of the screen.

If there is no other option I will have to stick with 2017r1 release as we have license for that release. Just that I will have to maintain 2 installations on my PC.

Let me know if you think I could try out some other stuff. I could send screen shots to explain the issue better if needed.

Regards Amit

Just in case:
I recently had a report of a possibly similar issue - a listbox with 200 items would not scroll.
It was my fault - I had recently added code in the mousedown which triggered a full refill of the listbox, and so it would never show the items at the bottom.

i agree that linux should behave same than windows.
have you made a test project with just dummy initial values at combobox?
its possible to carefully replace the “super” name in the form designer with a new container control name as replacement.
if the new cc have same visible propertys the ide should recycle all.