Microsoft-ui-xaml: SwipeControl (WUX/MUX) causes random crashes in ListView

[Sergio0694]

Describe the bug

Scrolling down a ListView with a large number of items, each having a SwipeControl in its template, randomly triggers a crash. By "randomly" I mean the crash happens when scrolling, at _some point_, which varies every time. The same crash happens with:

• A custom control which has the SwipeControl in its template
• The Windows.UI.Xaml.Controls.SwipeControl
• The Microsoft.UI.Xaml.Controls.SwipeControl (WinUI 2.4.2)

Steps to reproduce the bug

1. Download the repro: SwipeItemsCrashRepro.zip
2. Build and run the app
3. Scroll to the bottom, and eventually back up

NOTE: the repro uses the MarkdownTextBlock from the toolkit, which for some reason causes the crash to happen much more rapidly. Replacing it with just a TextBlock still causes the crash, but you then need to scroll up and down for quite a bit before observing the crash, for some reason.

I also prepared two crash dumps, one with the WUX control and one with the MUX one:

• Crash dump with Windows.UI.Xaml.Controls.SwipeItems
• Crash dump with Microsoft.UI.Xaml.Controls.SwipeItems

Expected behavior

Scrolling down the list should work as expected.

Screenshots

Version Info

NuGet package version:

• Microsoft.UI.Xaml 2.4.0

| Windows 10 version | Saw the problem? |
| :--------------------------------- | :-------------------- |
| Insider Build (19041.264) | Yes |
| November 2019 Update (18363) | |
| May 2019 Update (18362) | |
| October 2018 Update (17763) | |
| April 2018 Update (17134) | |
| Fall Creators Update (16299) | |
| Creators Update (15063) | |

| Device form factor | Saw the problem? |
| :-------------------- | :------------------- |
| Desktop | Yes |
| Mobile | |
| Xbox | |
| Surface Hub | |
| IoT | |

[ranjeshj]

@Sergio0694 Thanks for reporting. If you have a standalone repro app that you can share, that would be helpful. Thanks!

[Sergio0694]

Hey @ranjeshj, thank you for chiming in!
I've managed to create a minimal repro, I've added a link to the main post! 😊

[ranjeshj]

Hmm.. I'm not seeing the crash with the repro app with mouse wheel scroll or touch scroll. Does it crash immediately or take a while of usage ?

[Sergio0694]

Huh, that's weird. Yeah it's pretty much instantaneous for me, I can repro this 100% of the time both in my app and in the repro project I shared. You're on Windows 10 19041 too, correct?

@kikisaints Have you had a chance to try the repro to see if it crashes on your PC too?

[michael-hawker]

This crashed for me right away as soon as I grabbed the scrollbar and dragged down on 19041.

[StephenLPeters]

Removing needs-winui-3 because I suspect this is a swipe issue and could maybe be fixed before winui3

[Sergio0694]

Hey @StephenLPeters - that's amazing!
So glad to hear that, thank you for looking into this! 😊

[Felix-Dev]

Crash does not happen on 18363.836 with 18362 SDK.

[Sergio0694]

Thanks @Felix-Dev!
It really looks like this crash is only happening starting from Windows 10 19041 🤔

[ranjeshj]

@StephenLPeters @michael-hawker If you can repro this, can you share the native callstack for the crash ?

[Sergio0694]

Pinging @michael-hawker in case he missed the previous notification 😄

Also @kikisaints I was wondering if the two crash dumps I shared were useful?
Can't recall if I also shared them with @ranjeshj, in case I haven't and you'd like me to forward them to you just let me know!