VisualTreeHelper unable to traverse TeachingTip content

[HO-COOH]

Describe the bug

I am doing some customization using attached DependencyProperty, so I attached a Loaded event handler to a TeachingTip to traverse it with VisualTreeHelper, but it is unable to traverse the visual tree of it, giving no useful information.

Why is this important?

This should work

Steps to reproduce the bug

I have a TeachingTip defined in xaml

        <Button x:Name="Button" Click="Button_Click">Click to open tip</Button>
        <TeachingTip
            x:Name="MyTip"
            Loaded="MyTip_Loaded"
            LayoutUpdated="MyTip_LayoutUpdated"
            Content="Some tip"/>

0. Add a helper function to traverse a control and print it type name and name

static void printVisualTree(winrt::Microsoft::UI::Xaml::FrameworkElement const& element)
{
	if (!element)
		return;

	OutputDebugString(std::format(L"{}: {}\n", winrt::get_class_name(element), element.Name()).data());

	auto const numChild = winrt::Microsoft::UI::Xaml::Media::VisualTreeHelper::GetChildrenCount(element);
	for (auto i = 0; i < numChild; ++i)
	{
		printVisualTree(winrt::Microsoft::UI::Xaml::Media::VisualTreeHelper::GetChild(element, i).as<winrt::Microsoft::UI::Xaml::FrameworkElement>());
	}
}

1. Print out the visual tree in both Loaded and LayoutUpdated event

	void MainWindow::MyTip_Loaded(winrt::Windows::Foundation::IInspectable const& sender, winrt::Microsoft::UI::Xaml::RoutedEventArgs const& e)
	{
		auto teachingTip = sender.as<winrt::Microsoft::UI::Xaml::Controls::TeachingTip>();
		OutputDebugString(L"==============Loaded==========\n");
		printVisualTree(teachingTip);
	}

	void MainWindow::MyTip_LayoutUpdated(winrt::Windows::Foundation::IInspectable const& sender, winrt::Windows::Foundation::IInspectable const& e)
	{
		OutputDebugString(L"==============Layout Updated==========\n");
		printVisualTree(MyTip());
	}

Actual behavior

Gives

==============Layout Updated==========
Microsoft.UI.Xaml.Controls.TeachingTip: MyTip
Microsoft.UI.Xaml.Controls.Border: Container
==============Loaded==========
Microsoft.UI.Xaml.Controls.TeachingTip: MyTip
Microsoft.UI.Xaml.Controls.Border: Container

Expected behavior

No response

Screenshots

No response

NuGet package version

WinUI 3 - Windows App SDK 1.8.2: 1.8.251003001

Windows version

Windows 11 (24H2): Build 26100

Additional context

Full repro

[snigdha011997]

Hi @HO-COOH , can you please provide a minimal repro project to investigate the issue further?

[HO-COOH]

@snigdha011997 The original title is a bit misleading. I updated it and added a full repro link.