iOS bug view not updating correctly when Collection View is bound to an Observable Range Collection and visibility of view is set to true once collection loads

[krmWorkAccnt]

Description

This issue only exists on iOS and isn't an issue for Android.
Note -- There are a couple of different scenarios illustrating that it's not just one thing that is causing the issue.
The issue is with the View updating correctly when it's visibility is initially set to false in the constructor, then once the CollectionViews item source that is bound to an ObservableRangeCollection is populated and the Views visibility is set back to true, the CollectionViews items are not drawn to the view -- With this scenario, it's only an issue when the ObservableRangeCollection is directly being assigned e.g. Results = new ObservableRangeCollection(await GetData1()); -- However using below technique to populate the ObservableRangeCollection isn't an issue Results.AddRange(await GetData2());.
I have provided a project that replicates the issue and can be downloaded from https://github.com/krmWorkAccnt/iOSBugWithViewUpdatingAfterLoading
When the project loads, it's setup to show the issue with iOS -- To show it's a combination of events causing the issue, comment out the visibility setting in the constructor of the MainViewModel and populating the CollectionView using GetResults1() works correclty.

Steps to Reproduce

1. Refer to project and download -- created here: https://github.com/krmWorkAccnt/iOSBugWithViewUpdatingAfterLoading
2. files of interest are: MainViewModel.cs
3. Set the start up project as Android and run the project -- This will show there isn't an issue -- Set the start up project as iOS and run the project, this will show that there is an issue and after the collection views item source has been populated this isn't updating the view to be redrawn
4. For this set up, we're just assigning a collection directly to our collection property as per Results = new ObservableRangeCollection(await GetData1()); and setting the visibility to false in the VM constructor, however if you set the visibility to true in the constructor and run the project, the view draws items of the collection view correctly.
5. Set the visibility in the constructor back to false, then comment out where Results is being populated using GetData1 and uncomment below code where Results is using AddRange to populate the collection view, here the view is redrawn correctly.

Expected Behavior

iOS view draws correctly once the collection views item source has been updated and visibility is set back to true

Actual Behavior

iOS view isn't correctly redrawing once collection views item source is updated and visibility is set back to true

Basic Information

• Version with issue: 5.0.0.1874
• Last known good version: Not sure
• Platform Target Frameworks: iOS -- appears to be an issue for all platforms
  • iOS: 14.1
  • Android: 10 API 29
  • UWP: N/A
• Android Support Library / AndroidX Version:
• NuGet Packages: NETStandard.Library v2.0.3 -- Refractored.MvvMHelpers v1.6.2 -- Xamarin.Essentialsv1.5.3.2 -- Xamar.Forms v5.0.0.1874
• Affected Devices:
  iOS devices regardless of iOS version

Environment

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Reproduction Link

https://github.com/krmWorkAccnt/iOSBugWithViewUpdatingAfterLoading

Workaround

using AddRange to populate an ObservableRangeCollection that is bound to a collectionView

[Deepfreezed]

Looks like this is fixed in 5.0.0.2012 but now it's drawing both Empty and Item view #13794

[jfversluis]

Going to trust this is fixed then, we have a PR open for the other mentioned issue. If it's not, feel free to ping me or open a new issue and reference this one. Thanks!