CollectionView DisconnectHandler SelectionMode=Multiple Windows exception

[siem300]

Description

In our apps we have an issue with the DisconnectHandler of the CollectionView. When we call the DisconnectHandler method for the CollectionView when the SelectionMode is set to Multiple the apps throw an exception.

Exception:
{"PlatformView cannot be null here"}

The handler changes the selecteditems while it is being disconnected and this results in a change where the PlatformView is needed.

This issue only occurs on Windows. Android and iOS work as intended.

Steps to Reproduce

1. Start the attached reproduction project
2. Select either 'Navigate as modal' or 'Navigate'
3. Select one or more of the test strings
4. Select the 'Navigate back' button
5. App throws an exception but doesn't crash (in our case other code doesn't get executed because of this)

Link to public reproduction project repository

https://github.com/siem300/Maui-CollectionViewDisconnectHandlerWindows

Version with bug

8.0.60 SR6

Is this a regression from previous behavior?

Not sure, did not test other versions

Last version that worked well

Unknown/Other

Affected platforms

Windows

Affected platform versions

No response

Did you find any workaround?

A possible workaround is setting the selectionmode to none. The problem with this is that our page doesn't know which controls it is disconnecting so we have to type check them.

Relevant log output

at Microsoft.Maui.Handlers.ViewHandler`2.get_PlatformView()
   at Microsoft.Maui.Controls.Handlers.Items.ItemsViewHandler`1.get_ListViewBase()
   at Microsoft.Maui.Controls.Handlers.Items.SelectableItemsViewHandler`1.UpdateVirtualSelection()
   at Microsoft.Maui.Controls.Handlers.Items.SelectableItemsViewHandler`1.PlatformSelectionChanged(Object sender, SelectionChangedEventArgs args)
   at WinRT._EventSource_global__Microsoft_UI_Xaml_Controls_SelectionChangedEventHandler.EventState.<GetEventInvoke>b__1_0(Object sender, SelectionChangedEventArgs e)
   at ABI.Microsoft.UI.Xaml.Controls.SelectionChangedEventHandler.Do_Abi_Invoke(IntPtr thisPtr, IntPtr sender, IntPtr e)
--- End of stack trace from previous location ---

[github-actions]

Hi I'm an AI powered bot that finds similar issues based off the issue title.

Please view the issues below to see if they solve your problem, and if the issue describes your problem please consider closing this one and thumbs upping the other issue to help us prioritize it. Thank you!

Open similar issues:

• Using SelectionChangedCommand with CollectionView in Shell.FlyoutContent results in Win32 Unhandled Exception (#10041), similarity score: 0.76
• Multiple issues in iOS CollectionView selection synchronization (#14535), similarity score: 0.73

Closed similar issues:

• [Windows] Application crash when call a DisconnectHandler while remove the view. (#3787), similarity score: 0.76
• SelectionChangedCommand does not invoke in CollectionView twice when SelectionMode is Single on Windows (#15677), similarity score: 0.75
• Item Selected from ViewModel for CollectionView De-selected automatically (#15967), similarity score: 0.73

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[RoiChen001]

I can repro this issue at Windows platform on the latest 17.11.0 Preview 4.0 (8.0.70&8.0.60&8.0.40).