How to activate a local class by name, in C++/WinRT, in an unpackaged/unregistered application

[amtopel]

Hello, does anyone know how to instantiate a locally defined class by its name (or TypeName), in C++/WinRT, in an unpackaged/unregistered application? And preferably without using manifest-based activation.

winrt::get_activation_factory doesn't seem to work.

I feel like this is possible, though, because I've successfully passed a locally defined Page typename to Microsoft::UI::Xaml::Controls::Frame::Navigate, and it doesn't have any trouble instantiating the Page-derived class. So I'm wondering how the Frame is activating the Page behind the scenes.

Thanks for any info.

[lgztx96]

You may be interested in IXamlType: https://learn.microsoft.com/en-us/windows/windows-app-sdk/api/winrt/microsoft.ui.xaml.markup.ixamltype?view=windows-app-sdk-1.6

Behind the scenes, the XAML compiler automatically generates the supporting code.”

Usage

// =====================
// Get XAML type from the current App's MetadataProvider
// =====================
if (auto app = Application::Current())
{
	if (auto provider = app.try_as<winrt::Microsoft::UI::Xaml::Markup::IXamlMetadataProvider>())
	{
		winrt::Windows::UI::Xaml::Interop::TypeName name =
			winrt::xaml_typename<YourControl>();

		if (winrt::Microsoft::UI::Xaml::Markup::IXamlType xamlType = provider.GetXamlType(name))
		{
			auto instance = xamlType.ActivateInstance();
		}
	}
}

// =====================
// Get XAML type from a third-party component
// (XamlToolkit Labs for WinUI's MetadataProvider)
// =====================
// Requires <winrt/winrt::XamlToolkit::Labs::WinUI.h>
auto provider = winrt::XamlToolkit::Labs::WinUI::XamlMetaDataProvider();

winrt::Windows::UI::Xaml::Interop::TypeName name =
	winrt::xaml_typename<winrt::XamlToolkit::Labs::WinUI::MarkdownTextBlock>();

if (winrt::Microsoft::UI::Xaml::Markup::IXamlType xamlType = provider.GetXamlType(name))
{
	auto instance = xamlType.ActivateInstance();
}

[amtopel]

Thank you very much for that info. I really appreciate it.