Shell | Navigation

All navigation in Shiny Shell goes through the INavigator interface. Inject it into your ViewModels via constructor injection.

public class MyViewModel(INavigator navigator)
{
    // navigator is ready to use
}

NavigateTo (Route)

Navigate to a registered route by name, optionally passing arguments as key-value tuples.

// Simple route navigation
await navigator.NavigateTo("details");

// With arguments
await navigator.NavigateTo("details", ("Id", 42), ("Name", "Allan"));

Arguments are received on the target ViewModel via IQueryAttributable.ApplyQueryAttributes.

NavigateTo (ViewModel)

Navigate by ViewModel type with an optional configuration action for strongly-typed argument passing.

// Navigate to a ViewModel
await navigator.NavigateTo<DetailViewModel>();

// With strongly-typed property setup
await navigator.NavigateTo<DetailViewModel>(vm => vm.Id = 42);

// With additional route arguments
await navigator.NavigateTo<DetailViewModel>(
    vm => vm.Id = 42,
    ("ExtraArg", "value")
);

Note

If you are setting properties on the ViewModel during navigation, those properties should be observable (e.g. use [ObservableProperty] or raise PropertyChanged) if they are bound on the Page.

Relative Navigation

Both NavigateTo overloads accept a relativeNavigation parameter (default true). When set to false, the URI is prefixed with // to navigate from the root, replacing the navigation stack.

// Relative navigation (default) — pushes onto the stack
await navigator.NavigateTo("details");
await navigator.NavigateTo<DetailViewModel>();

// Root navigation — resets to root and navigates
await navigator.NavigateTo("dashboard", relativeNavigation: false);
await navigator.NavigateTo<DashboardViewModel>(relativeNavigation: false);

// With configuration
await navigator.NavigateTo<DashboardViewModel>(
    vm => vm.WelcomeMessage = "Hello!",
    relativeNavigation: false
);

Caution

Root navigation (relativeNavigation: false or CreateBuilder(fromRoot: true)) uses the // URI prefix, which requires the target route to be declared in your AppShell.xaml (or other Shell XAML). Routes registered only via Routing.RegisterRoute (or [ShellMap] with registerRoute: true) cannot be navigated to from root — Shell will throw a navigation error.

If you need a page to support root navigation, add it as a ShellContent in your Shell XAML and use registerRoute: false in [ShellMap]:

<ShellContent ContentTemplate="{DataTemplate local:DashboardPage}" Route="DashboardPage" />

[ShellMap<DashboardPage>(registerRoute: false)]
public class DashboardViewModel { }

Navigation Builder

The INavigationBuilder provides a fluent API for constructing multi-segment navigation URIs in a single call. Create one via INavigator.CreateBuilder().

// Push three pages in one navigation: ChainPage/DetailPage/ChainPage
await navigator
    .CreateBuilder()
    .Add<ChainViewModel>(x => x.Text = "Page1")
    .Add<DetailViewModel>(x => x.Id = 42)
    .Add<ChainViewModel>(x => x.Text = "Page3")
    .Navigate();

// Pop back 2 pages, then push a new page: ../../ChainPage
await navigator
    .CreateBuilder()
    .PopBack(2)
    .Add<ChainViewModel>(x => x.Text = "After Pop")
    .Navigate();

// Navigate from root: //ChainPage/DetailPage
await navigator
    .CreateBuilder(fromRoot: true)
    .Add<ChainViewModel>(x => x.Text = "Root Start")
    .Add<DetailViewModel>(x => x.Id = 1)
    .Navigate();

// Mix string routes and ViewModel-based segments
await navigator
    .CreateBuilder()
    .Add("settings")
    .Add<DetailViewModel>(x => x.Id = 99)
    .Navigate();

Method	Description
CreateBuilder(bool fromRoot)	Creates a builder. fromRoot: true prefixes the URI with //
PopBack(int count)	Adds .. pop segments. Must be called before any Add calls. Not valid with fromRoot: true
Add<TViewModel>()	Adds a route segment for the ViewModel type
Add<TViewModel>(configure)	Adds a route segment with a configure callback invoked when the page is created
Add(string routeName)	Adds a raw route string segment
Navigate()	Builds the URI and executes the navigation

Note

When using source-generated extensions, typed Add methods are generated for each [ShellMap] ViewModel. For example, [ShellMap<ChainPage>] with [ShellProperty] Text generates AddChain(string text) on INavigationBuilder.

Caution

When using CreateBuilder(fromRoot: true), the first route segment must be declared in your Shell XAML — see the Relative Navigation section for details.

GoBack

Navigate back one or more pages, optionally passing arguments to the previous ViewModel.

// Simple go back
await navigator.GoBack();

// Go back with arguments
await navigator.GoBack(("Result", "saved"), ("Timestamp", DateTime.UtcNow));

// Go back multiple pages
await navigator.GoBack(2);

// Go back multiple pages with arguments
await navigator.GoBack(2, ("Result", "saved"));

PopToRoot

Pop the entire navigation stack back to the root page.

await navigator.PopToRoot();

// With arguments
await navigator.PopToRoot(("Status", "complete"));

SwitchShell

Replace the entire active Shell at runtime. Useful for switching between different app experiences (e.g. tabbed layout, flyout menu, onboarding flow).

// Switch to a new Shell instance
await navigator.SwitchShell(new AdminShell());

// Switch to a Shell resolved from DI
await navigator.SwitchShell<AdminShell>();

The current Shell’s ViewModel receives OnNavigatingFrom before the switch, and the Navigating event fires with NavigationType.SwitchShell.

Note

The new Shell must be a fresh instance — do not reuse a Shell that was previously displayed. Shell instances resolved via SwitchShell<TShell>() are created from the DI container each time.

Tab Badges

INavigator can set and clear numeric badges on tabs that already exist in the active Shell.

// By route
await navigator.SetTabBadge("Inbox", 3);
await navigator.ClearTabBadge("Inbox");

// By ViewModel mapping
await navigator.SetTabBadge<InboxViewModel>(7);
await navigator.ClearTabBadge<InboxViewModel>();

Note

The target route must already be present as a tab in the active Shell. Tab badges are supported on Android, iOS, Mac Catalyst, and Windows. Linux and macOS AppKit throw PlatformNotSupportedException.

XAML Navigation

For route-based navigation from XAML, use the Navigate attached properties instead of a ViewModel command.

<Button Text="Open Detail"
        shiny:Navigate.Route="Detail"
        shiny:Navigate.ParameterKey="ItemId"
        shiny:Navigate.ParameterValue="{Binding SelectedId}" />

RelativeNavigation defaults to true. Set it to false for root navigation:

<ToolbarItem Text="Home"
             shiny:Navigate.Route="MainPage"
             shiny:Navigate.RelativeNavigation="False" />

For multiple parameters:

<Button Text="Open Modal"
        shiny:Navigate.Route="modal">
    <shiny:Navigate.Parameters>
        <shiny:NavigationParameters>
            <shiny:NavigationParameter Key="Arg1" Value="{Binding NavArg}" />
            <shiny:NavigationParameter Key="Arg2" Value="5" />
        </shiny:NavigationParameters>
    </shiny:Navigate.Parameters>
</Button>

Note

Navigate currently supports Button, MenuItem, and ToolbarItem.

Navigation Events

INavigator exposes two events for observing navigation lifecycle:

Navigating (Pre-Navigation)

Fires before navigation occurs. Provides the source ViewModel instance and destination route.

navigator.Navigating += (sender, args) =>
{
    // args.FromUri         — current location URI
    // args.FromViewModel   — source ViewModel instance (object?)
    // args.ToUri           — destination route URI
    // args.NavigationType  — Push, SetRoot, GoBack, PopToRoot, or SwitchShell
    // args.Parameters      — navigation parameters
};

Property	Type	Description
FromUri	string?	The current Shell location URI
FromViewModel	object?	The source page’s ViewModel instance
ToUri	string	The destination route URI
NavigationType	NavigationType	Push, SetRoot, GoBack, PopToRoot, or SwitchShell
Parameters	IReadOnlyDictionary<string, object>	Navigation parameters

Navigated (Post-Navigation)

Fires after navigation completes and the destination page’s ViewModel is resolved.

navigator.Navigated += (sender, args) =>
{
    // args.ToUri           — destination route URI
    // args.ToViewModel     — destination ViewModel instance (object?)
    // args.NavigationType  — Push, SetRoot, GoBack, PopToRoot, or SwitchShell
    // args.Parameters      — navigation parameters
};

Property	Type	Description
ToUri	string	The destination route URI
ToViewModel	object?	The destination page’s ViewModel instance
NavigationType	NavigationType	Push, SetRoot, GoBack, PopToRoot, or SwitchShell
Parameters	IReadOnlyDictionary<string, object>	Navigation parameters

Example: Navigation Logger

Use IMauiInitializeService to hook events for cross-cutting concerns like logging or analytics:

public class NavigationLogger(
    ILogger<NavigationLogger> logger,
    INavigator navigator
) : IMauiInitializeService
{
    public void Initialize(IServiceProvider services)
    {
        navigator.Navigating += (_, args) =>
        {
            logger.LogInformation(
                "Navigating from '{FromUri}' to '{ToUri}' | Type: {NavigationType} | FromViewModel: {FromViewModel}",
                args.FromUri,
                args.ToUri,
                args.NavigationType,
                args.FromViewModel?.GetType().Name
            );
        };

        navigator.Navigated += (_, args) =>
        {
            logger.LogInformation(
                "Navigated to '{ToUri}' | Type: {NavigationType} | ToViewModel: {ToViewModel}",
                args.ToUri,
                args.NavigationType,
                args.ToViewModel?.GetType().Name
            );
        };
    }
}

// Register in MauiProgram.cs
builder.Services.AddSingleton<IMauiInitializeService, NavigationLogger>();

Passing Arguments

Arguments passed during navigation are delivered via the MAUI built-in IQueryAttributable interface.

public class DetailViewModel : IQueryAttributable
{
    public int Id { get; set; }

    public void ApplyQueryAttributes(IDictionary<string, object> query)
    {
        if (query.TryGetValue("Id", out var id))
            Id = (int)id;
    }
}

This works for arguments passed via NavigateTo, GoBack, and PopToRoot.

Tip

When using ViewModel-based navigation (NavigateTo<TViewModel>), you can skip IQueryAttributable entirely and set properties directly via the configuration action. This is the recommended approach for strongly-typed navigation.