CollectionView does not update layout correctly when ItemsSource changes

[APopatanasov]

Description

I have a page that contains a CollectionView. Based on some input, I update its ItemsSource. However, when the CollectionView is initially arranged with a height of zero, updating the ItemsSource and invalidating the measure still results in a measured height of zero.

This issue appears to be related to the switch from CollectionViewHandler to CollectionViewHandler2 as the default handler for iOS/Catalyst. When I revert to using the original CollectionViewHandler, the layout behaves as expected.

Steps to Reproduce

1. Run the provided sample project.
2. Type for example "G" in the entry.

Expected Behavior
The CollectionView should visualize a single item "Germany".

Actual Behavior
The CollectionView doesn't visualize any item and measure returns zero.

Link to public reproduction project repository

https://github.com/telerik/ms-samples/tree/main/Maui/CollectionViewItemsSourceNet10Issue

Version with bug

10.0.0-preview.6

Is this a regression from previous behavior?

Yes, this used to work in .NET MAUI

Last version that worked well

9.0.90 SR9

Affected platforms

iOS, macOS

Affected platform versions

No response

Did you find any workaround?

If you switch back to CollectionViewHandler instead of using CollectionViewHandler2 everything is working as expected.

[deepika2509]

This issue has been verified in Visual Studio Code 1.102.2 with MAUI versions 9.0.90, 10.0.0.Preview.1 & 10.0.0.Preview.6. It can be reproduced on iOS and MacCatalyst platforms with CV2 handler.

Note: This issue not happens in CV1 handler.