[Bug] CollectionView item renderers never get disposed on Android (Memory Leak)

[billvenhaus]

Description

On Android, the item renderers of a CollectionView never get disposed. Dispose is only called on the CollectionView renderer itself. Its children, the item renderers, are ignored. This can lead to potential memory leaks.

This is not an issue on iOS or UWP. It's only an issue on Android. Dispose is called on the item renderers for iOS and UWP.

Steps to Reproduce

Place a breakpoint inside the Dispose method for any child/item renderer used by the CollectionView.

I have created an example to easily demonstrate the issue:

1. Place breakpoints in the Dispose method of MyCheckBoxRenderer.cs
2. Click Open Test
3. Click the Back button to close Test page
4. Does the breakpoint halt the program? If so, good. The Dispose method was called.

Expected Behavior

When the CollectionView is disposed, its active item/child renderers should also be disposed.

Actual Behavior

When the CollectionView is disposed, its active item/child renderers are never disposed on Android.

iOS & UWP work. Dispose is called on item/child renderers for iOS & UWP apps.

Basic Information

• Version with issue: 5.0.0.2196
• Last known good version: NA
• Platform Target Frameworks:
  • iOS: 15.0 (tested and works as expected)
  • Android: 11.0 (tested and does not work)
  • UWP: tested 16299 (tested and works as expected)
• Affected Devices: Any Android device.

Environment

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Microsoft Visual Studio Community 2019
Version 16.11.6
VisualStudio.16.Release/16.11.6+31829.152
Microsoft .NET Framework
Version 4.8.04084

Installed Version: Community

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Azure Functions and Web Jobs Tools

C# Tools   3.11.0-4.21403.6+ae1fff344d46976624e68ae17164e0607ab68b10
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Common Azure Tools   1.10
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Xamarin.iOS and Xamarin.Mac SDK   15.0.0.8 (0796d78dc)
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Screenshots

Reproduction Link

https://github.com/billvenhaus/CollectionViewDisposal