VisualDiagnostics.VisualTreeChanged returns null parent elements, -1 Child Index Values, for new items.

[drasticactions]

Description

Some parent elements being sent to VisualDiagnostics.VisualTreeChanged for new items are null, resulting in -1 Child Index values. Checking the children values, the parent is null there too. This seems to happen consistently for

• App (I think that's valid, the App is the top of the stack)
• New Pages
• New Views
• New Item Templates

As far as I can tell, this is not a regression. I think it's always done from early in MAUIs history. This doesn't break tools like XAML Hot Reload, but we need to recalculate the visual tree for these elements and that can be costly to do.

Steps to Reproduce

1. Clone https://github.com/davidortinau/AllTheLists
2. Load the App in VS/VSCode
3. Open the XAML/C# Hot Reload Log list
4. See the logs for ChildIndex <= -1. These are due to null parents being passed in through the MAUI EventHandler.
5. Or put a breakpoint in VisualDiagnostics.VisualTreeChanged in MAUI and see that parent is null.

Or

1. Create a new app with two pages
2. Hook into VisualDiagnostics.VisualTreeChanged

Link to public reproduction project repository

https://github.com/davidortinau/AllTheLists

Version with bug

8.0.40 SR5

Is this a regression from previous behavior?

No, this is something new

Last version that worked well

Unknown/Other

Affected platforms

iOS, Android, Windows, macOS

Affected platform versions

No response

Did you find any workaround?

No response

Relevant log output

No response

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