BetterWinUI.DependencyInjection.PageActivation 0.1.2

BetterWinUI.DependencyInjection.PageActivation

NativeAOT-compatible constructor injection for WinUI Page navigation.

You can register explicitly in the DI composition root:

public App()
{
    var services = new ServiceCollection();
    services.AddTransient<MainViewModel>();
    services.AddTransient<MainPage>();
    services.AddBetterPageActivation();

    Services = services.BuildServiceProvider();
    this.InitializeBetterPageActivation(Services);
}

public ServiceProvider Services { get; }

public sealed partial class MainPage : Page
{
    public MainPage(MainViewModel viewModel)
    {
        InitializeComponent();
        ViewModel = viewModel;
    }

    public MainViewModel ViewModel { get; }
}

public sealed class MainViewModel;

Or, you can use the optional registration attributes:

[View] // ServiceLifetime.Transient by default
public sealed partial class MainPage : Page
{
    public MainPage(MainViewModel viewModel)
    {
        InitializeComponent();
        ViewModel = viewModel;
    }

    public MainViewModel ViewModel { get; }
}

[ViewModel(ServiceLifetime.Transient)]
public sealed class MainViewModel;

[View] and [ViewModel] are independent registration syntax sugar; they do not declare a navigation or View-to-ViewModel relationship.

Generated registrations use standard Microsoft DI descriptors and TryAdd, so explicit registrations already present in the service collection are preserved. Constructor selection and keyed constructor dependencies remain container-owned. The package does not assign DataContext.

Unregistered Pages throw by default. Native XAML activation can be enabled explicitly:

services.AddBetterPageActivation(static options =>
{
    options.UnregisteredPageBehavior =
        UnregisteredPageBehavior.FallbackToXamlActivator;
});

Call InitializeBetterPageActivation exactly once after the service provider is built and before navigating to a Page.

ServiceLifetime.Scoped is rejected until navigation scope ownership and disposal are defined.

Diagnostics

BWPA0001

The application type must be declared partial so the generator can extend it.

BWPA0002

[PageActivation] must target a concrete, non-generic, top-level WinUI Application subclass.

BWPA0003

Only one application type per assembly can use [PageActivation].

BWPA0004

The XAML compiler output must expose one native IXamlMetadataProvider property on the application type.

BWPA0005

Rename a user-declared InitializeBetterPageActivation member so the generator can emit its initialization method.

BWPA0006

[View] must target an accessible, concrete, non-generic WinUI Page subclass.

BWPA0007

[ViewModel] must target an accessible, concrete, non-abstract, closed class.

BWPA0009

Generated registrations cannot use ServiceLifetime.Scoped until navigation scope ownership and disposal are implemented.

BWPA0010

A referenced generated view module uses an incompatible page activation contract version.

BWPA0011

The generated ViewModel registration has no public constructor; provide an explicit DI factory before calling AddBetterPageActivation.

BWPA0012

No InitializeBetterPageActivation call was found for the application type.

BWPA0013

The referenced Windows App SDK XAML interfaces do not expose the interception contract required by the generator.

BWPA0014

The generated Page registration has no public constructor; provide an explicit DI factory before calling AddBetterPageActivation.

BWPA0015

Generated registrations support only ServiceLifetime.Transient and ServiceLifetime.Singleton.