Axiom Swiftui Nav Ref

SwiftUI Navigation API Reference

Overview

SwiftUI's navigation APIs provide data-driven, programmatic navigation that scales from simple stacks to complex multi-column layouts. Introduced in iOS 16 (2022) with NavigationStack and NavigationSplitView, evolved in iOS 18 (2024) with Tab/Sidebar unification, and refined in iOS 26 (2025) with Liquid Glass design.

Evolution timeline

• 2022 (iOS 16) NavigationStack, NavigationSplitView, NavigationPath, value-based NavigationLink
• 2024 (iOS 18) Tab/Sidebar unification, sidebarAdaptable style, zoom navigation transition
• 2025 (iOS 26) Liquid Glass navigation chrome, bottom-aligned search, floating tab bars, backgroundExtensionEffect

Key capabilities

• Data-driven navigation NavigationPath represents stack state, enabling programmatic push/pop and deep linking
• Multi-column layouts NavigationSplitView adapts automatically (3-column on iPad → single stack on iPhone)
• State restoration Codable NavigationPath + SceneStorage for persistence across app launches
• Tab integration Per-tab NavigationStack with state preservation on tab switch (iOS 18+)
• Liquid Glass Automatic glass navigation bars, sidebars, and toolbars (iOS 26+)

When to use vs UIKit

• SwiftUI navigation New apps, multiplatform, simpler navigation flows → Use NavigationStack/SplitView
• UINavigationController Complex coordinator patterns, legacy code, specific UIKit features → Consider UIKit

Related Skills

• Use axiom-swiftui-nav for anti-patterns, decision trees, pressure scenarios
• Use axiom-swiftui-nav-diag for systematic troubleshooting of navigation issues

When to Use This Skill

Use this skill when:

• Learning navigation APIs from NavigationStack to NavigationSplitView to NavigationPath
• Implementing WWDC examples (all 4 sessions with code examples included)
• Planning deep linking with URL routing and NavigationPath manipulation
• Setting up state restoration with Codable NavigationPath and SceneStorage
• Adopting iOS 26+ features Liquid Glass navigation, bottom-aligned search, tab bar minimization
• Choosing navigation architecture Stack vs SplitView vs Tab+Navigation patterns
• Implementing coordinator/router patterns alongside SwiftUI's built-in navigation

API Evolution

Timeline

NavigationView (Deprecated) vs NavigationStack/SplitView

Recommendation

• New apps: Use NavigationStack and NavigationSplitView exclusively
• Existing apps: Migrate from NavigationView (deprecated)
• See "Migrating to new navigation types" documentation

NavigationStack Complete Reference

NavigationStack represents a push-pop interface like Settings on iPhone or System Settings on macOS.

1.1 Creating NavigationStack

Basic NavigationStack

NavigationStack {
    List(Category.allCases) { category in
        NavigationLink(category.name, value: category)
    }
    .navigationTitle("Categories")
    .navigationDestination(for: Category.self) { category in
        CategoryDetail(category: category)
    }
}

With Path Binding (WWDC 2022, 6:05)

struct PushableStack: View {
    @State private var path: [Recipe] = []
    @StateObject private var dataModel = DataModel()

    var body: some View {
        NavigationStack(path: $path) {
            List(Category.allCases) { category in
                Section(category.localizedName) {
                    ForEach(dataModel.recipes(in: category)) { recipe in
                        NavigationLink(recipe.name, value: recipe)
                    }
                }
            }
            .navigationTitle("Categories")
            .navigationDestination(for: Recipe.self) { recipe in
                RecipeDetail(recipe: recipe)
            }
        }
        .environmentObject(dataModel)
    }
}

Key points:

• path: $path binds the navigation state to a collection
• Value-presenting NavigationLink appends values to the path
• navigationDestination(for:) maps values to views

1.2 NavigationLink (Value-Based)

Value-presenting NavigationLink

// Correct: Value-based (iOS 16+)
NavigationLink(recipe.name, value: recipe)

// Correct: With custom label
NavigationLink(value: recipe) {
    RecipeTile(recipe: recipe)
}

// Deprecated: View-based (iOS 13-15)
NavigationLink(recipe.name) {
    RecipeDetail(recipe: recipe)  // Don't use in new code
}

How NavigationLink works with NavigationStack

1. NavigationStack maintains a path collection
2. Tapping a value-presenting link appends the value to the path
3. NavigationStack maps navigationDestination modifiers over path values
4. Views are pushed onto the stack based on destination mappings

1.3 navigationDestination Modifier

Single Type

.navigationDestination(for: Recipe.self) { recipe in
    RecipeDetail(recipe: recipe)
}

Multiple Types

NavigationStack(path: $path) {
    RootView()
        .navigationDestination(for: Recipe.self) { recipe in
            RecipeDetail(recipe: recipe)
        }
        .navigationDestination(for: Category.self) { category in
            CategoryList(category: category)
        }
        .navigationDestination(for: Chef.self) { chef in
            ChefProfile(chef: chef)
        }
}

Placement rules

• Place navigationDestination outside lazy containers (not inside ForEach)
• Place near related NavigationLinks for code organization
• Must be inside NavigationStack hierarchy

// Correct: Outside lazy container
ScrollView {
    LazyVGrid(columns: columns) {
        ForEach(recipes) { recipe in
            NavigationLink(value: recipe) {
                RecipeTile(recipe: recipe)
            }
        }
    }
}
.navigationDestination(for: Recipe.self) { recipe in
    RecipeDetail(recipe: recipe)
}

// Wrong: Inside ForEach (may not be loaded)
ForEach(recipes) { recipe in
    NavigationLink(value: recipe) { RecipeTile(recipe: recipe) }
        .navigationDestination(for: Recipe.self) { r in  // Don't do this
            RecipeDetail(recipe: r)
        }
}

1.4 NavigationPath

NavigationPath is a type-erased collection for heterogeneous navigation stacks.

Typed Array vs NavigationPath

// Typed array: All values same type
@State private var path: [Recipe] = []

// NavigationPath: Mixed types
@State private var path = NavigationPath()

NavigationPath Operations

// Append value
path.append(recipe)

// Pop to previous
path.removeLast()

// Pop to root
path.removeLast(path.count)
// or
path = NavigationPath()

// Check count
if path.count > 0 { ... }

// Deep link: Set multiple values
path.append(category)
path.append(recipe)

Codable Support

// NavigationPath is Codable when all values are Codable
@State private var path = NavigationPath()

// Encode
let data = try JSONEncoder().encode(path.codable)

// Decode
let codableRep = try JSONDecoder().decode(NavigationPath.CodableRepresentation.self, from: data)
path = NavigationPath(codableRep)

NavigationSplitView Complete Reference

NavigationSplitView creates multi-column layouts that adapt to device size.

2.1 Two-Column Layout

Basic Two-Column (WWDC 2022, 10:40)

struct MultipleColumns: View {
    @State private var selectedCategory: Category?
    @State private var selectedRecipe: Recipe?
    @StateObject private var dataModel = DataModel()

    var body: some View {
        NavigationSplitView {
            List(Category.allCases, selection: $selectedCategory) { category in
                NavigationLink(category.localizedName, value: category)
            }
            .navigationTitle("Categories")
        } detail: {
            if let recipe = selectedRecipe {
                RecipeDetail(recipe: recipe)
            } else {
                Text("Select a recipe")
            }
        }
    }
}

2.2 Three-Column Layout

Three-Column with Content Column

NavigationSplitView {
    // Sidebar
    List(Category.allCases, selection: $selectedCategory) { category in
        NavigationLink(category.localizedName, value: category)
    }
    .navigationTitle("Categories")
} content: {
    // Content column
    List(dataModel.recipes(in: selectedCategory), selection: $selectedRecipe) { recipe in
        NavigationLink(recipe.name, value: recipe)
    }
    .navigationTitle(selectedCategory?.localizedName ?? "Recipes")
} detail: {
    // Detail column
    RecipeDetail(recipe: selectedRecipe)
}

2.3 NavigationSplitView with NavigationStack (WWDC 2022, 14:10)

Combine split view selection with stack-based drill-down:

struct MultipleColumnsWithStack: View {
    @State private var selectedCategory: Category?
    @State private var path: [Recipe] = []
    @StateObject private var dataModel = DataModel()

    var body: some View {
        NavigationSplitView {
            List(Category.allCases, selection: $selectedCategory) { category in
                NavigationLink(category.localizedName, value: category)
            }
            .navigationTitle("Categories")
        } detail: {
            NavigationStack(path: $path) {
                RecipeGrid(category: selectedCategory)
                    .navigationDestination(for: Recipe.self) { recipe in
                        RecipeDetail(recipe: recipe)
                    }
            }
        }
        .environmentObject(dataModel)
    }
}

Key pattern: NavigationStack inside NavigationSplitView detail column enables grid-to-detail drill-down while preserving sidebar selection.

2.4 Column Visibility

@State private var columnVisibility: NavigationSplitViewVisibility = .all

NavigationSplitView(columnVisibility: $columnVisibility) {
    Sidebar()
} content: {
    Content()
} detail: {
    Detail()
}

// Programmatically control visibility
columnVisibility = .detailOnly  // Hide sidebar and content
columnVisibility = .all          // Show all columns
columnVisibility = .automatic    // System decides

2.5 Automatic Adaptation

NavigationSplitView automatically adapts:

• iPad landscape All columns visible (depending on configuration)
• iPad portrait/Slide Over Collapses to overlay or single column
• iPhone Single navigation stack
• Apple Watch/TV Single navigation stack

Selection changes automatically translate to push/pop on iPhone.

2.6 iOS 26+ Liquid Glass Sidebar (WWDC 2025, 323)

NavigationSplitView {
    List { ... }
} detail: {
    DetailView()
}
// Sidebar automatically gets Liquid Glass appearance on iPad/macOS

// Extend content behind glass sidebar
.backgroundExtensionEffect()  // Mirrors and blurs content outside safe area

Deep Linking and URL Routing

3.1 Basic Deep Link Handling

struct ContentView: View {
    @State private var path = NavigationPath()

    var body: some View {
        NavigationStack(path: $path) {
            HomeView()
                .navigationDestination(for: Recipe.self) { recipe in
                    RecipeDetail(recipe: recipe)
                }
                .navigationDestination(for: Category.self) { category in
                    CategoryView(category: category)
                }
        }
        .onOpenURL { url in
            handleDeepLink(url)
        }
    }

    func handleDeepLink(_ url: URL) {
        // Parse URL: myapp://recipe/apple-pie
        guard let components = URLComponents(url: url, resolvingAgainstBaseURL: false),
              let host = components.host else { return }

        switch host {
        case "recipe":
            if let recipeName = components.path.dropFirst().description,
               let recipe = dataModel.recipe(named: recipeName) {
                path.removeLast(path.count)  // Pop to root
                path.append(recipe)           // Push recipe
            }
        case "category":
            if let categoryName = components.path.dropFirst().description,
               let category = Category(rawValue: categoryName) {
                path.removeLast(path.count)
                path.append(category)
            }
        default:
            break
        }
    }
}

3.2 Multi-Step Deep Links

// URL: myapp://category/desserts/recipe/apple-pie
func handleDeepLink(_ url: URL) {
    let pathComponents = url.pathComponents.filter { $0 != "/" }

    path.removeLast(path.count)  // Reset to root

    var index = 0
    while index < pathComponents.count {
        let component = pathComponents[index]

        switch component {
        case "category":
            if index + 1 < pathComponents.count,
               let category = Category(rawValue: pathComponents[index + 1]) {
                path.append(category)
                index += 2
            }
        case "recipe":
            if index + 1 < pathComponents.count,
               let recipe = dataModel.recipe(named: pathComponents[index + 1]) {
                path.append(recipe)
                index += 2
            }
        default:
            index += 1
        }
    }
}

State Restoration

4.1 Complete State Restoration (WWDC 2022, 18:12)

struct UseSceneStorage: View {
    @StateObject private var navModel = NavigationModel()
    @SceneStorage("navigation") private var data: Data?
    @StateObject private var dataModel = DataModel()

    var body: some View {
        NavigationSplitView {
            List(Category.allCases, selection: $navModel.selectedCategory) { category in
                NavigationLink(category.localizedName, value: category)
            }
            .navigationTitle("Categories")
        } detail: {
            NavigationStack(path: $navModel.recipePath) {
                RecipeGrid(category: navModel.selectedCategory)
            }
        }
        .task {
            // Restore on appear
            if let data = data {
                navModel.jsonData = data
            }
            // Save on changes
            for await _ in navModel.objectWillChangeSequence {
                data = navModel.jsonData
            }
        }
        .environmentObject(dataModel)
    }
}

4.2 Codable NavigationModel

class NavigationModel: ObservableObject, Codable {
    @Published var selectedCategory: Category?
    @Published var recipePath: [Recipe] = []

    enum CodingKeys: String, CodingKey {
        case selectedCategory
        case recipePathIds  // Store IDs, not full objects
    }

    func encode(to encoder: Encoder) throws {
        var container = encoder.container(keyedBy: CodingKeys.self)
        try container.encodeIfPresent(selectedCategory, forKey: .selectedCategory)
        try container.encode(recipePath.map(\.id), forKey: .recipePathIds)
    }

    init() {}

    required init(from decoder: Decoder) throws {
        let container = try decoder.container(keyedBy: CodingKeys.self)
        self.selectedCategory = try container.decodeIfPresent(Category.self, forKey: .selectedCategory)

        // Convert IDs back to objects, discarding deleted items
        let recipePathIds = try container.decode([Recipe.ID].self, forKey: .recipePathIds)
        self.recipePath = recipePathIds.compactMap { DataModel.shared[$0] }
    }

    var jsonData: Data? {
        get { try? JSONEncoder().encode(self) }
        set {
            guard let data = newValue,
                  let model = try? JSONDecoder().decode(NavigationModel.self, from: data)
            else { return }
            self.selectedCategory = model.selectedCategory
            self.recipePath = model.recipePath
        }
    }

    var objectWillChangeSequence: AsyncPublisher<Publishers.Buffer<ObservableObjectPublisher>> {
        objectWillChange
            .buffer(size: 1, prefetch: .byRequest, whenFull: .dropOldest)
            .values
    }
}

Key pattern: Store IDs, not full model objects. Use compactMap to handle deleted items gracefully.

Tab + Navigation Integration

5.1 Tab Syntax (iOS 18+) (WWDC 2024, 4:27)

TabView {
    Tab("Watch Now", systemImage: "play") {
        WatchNowView()
    }
    Tab("Library", systemImage: "books.vertical") {
        LibraryView()
    }
    Tab(role: .search) {
        NavigationStack {
            SearchView()
                .navigationTitle("Search")
        }
        .searchable(text: $searchText)
    }
}

Search tab requirement: Contents of a search-role tab must be wrapped in NavigationStack with .searchable() applied to the stack. Without NavigationStack, the search field will not appear. For foundational .searchable patterns (suggestions, scopes, tokens, programmatic control), see axiom-swiftui-search-ref.

5.2 TabView with NavigationStack Per Tab

TabView {
    Tab("Home", systemImage: "house") {
        NavigationStack {
            HomeView()
                .navigationDestination(for: Item.self) { item in
                    ItemDetail(item: item)
                }
        }
    }
    Tab("Settings", systemImage: "gear") {
        NavigationStack {
            SettingsView()
        }
    }
}

Key pattern: Each tab has its own NavigationStack to preserve navigation state when switching tabs.

5.3 Sidebar-Adaptable TabView (WWDC 2024, 6:41)

TabView {
    Tab("Watch Now", systemImage: "play") {
        WatchNowView()
    }
    Tab("Library", systemImage: "books.vertical") {
        LibraryView()
    }
    TabSection("Collections") {
        Tab("Cinematic Shots", systemImage: "list.and.film") {
            CinematicShotsView()
        }
        Tab("Forest Life", systemImage: "list.and.film") {
            ForestLifeView()
        }
    }
    TabSection("Animations") {
        // More tabs...
    }
    Tab(role: .search) {
        SearchView()
    }
}
.tabViewStyle(.sidebarAdaptable)

Key features:

• TabSection creates groups visible in sidebar
• .sidebarAdaptable enables sidebar on iPad, tab bar on iPhone
• Search tab with .search role gets special placement

5.4 Tab Customization (WWDC 2024, 10:45)

@AppStorage("MyTabViewCustomization")
private var customization: TabViewCustomization

TabView {
    Tab("Watch Now", systemImage: "play", value: .watchNow) {
        WatchNowView()
    }
    .customizationID("Tab.watchNow")
    .customizationBehavior(.disabled, for: .sidebar, .tabBar)  // Can't be hidden

    Tab("Optional Tab", systemImage: "star", value: .optional) {
        OptionalView()
    }
    .customizationID("Tab.optional")
    .defaultVisibility(.hidden, for: .tabBar)  // Hidden by default
}
.tabViewCustomization($customization)

5.5 Programmatic Tab Visibility

Use .hidden(_:) to show/hide tabs based on app state while preserving their navigation state.

State-Driven Tab Visibility

enum AppContext { case home, browse }

struct ContentView: View {
    @State private var context: AppContext = .home
    @State private var selection: TabID = .home

    var body: some View {
        TabView(selection: $selection) {
            Tab("Home", systemImage: "house") {
                HomeView()
            }
            .tag(TabID.home)

            Tab("Libraries", systemImage: "square.stack") {
                LibrariesView()
            }
            .tag(TabID.libraries)
            .hidden(context == .browse)  // Hide in browse context

            Tab("Playlists", systemImage: "music.note.list") {
                PlaylistsView()
            }
            .tag(TabID.playlists)
            .hidden(context == .browse)

            Tab("Tracks", systemImage: "music.note") {
                TracksView()
            }
            .tag(TabID.tracks)
            .hidden(context == .home)    // Hide in home context
        }
        .tabViewStyle(.sidebarAdaptable)
    }
}

State Preservation

Key difference: .hidden(_:) preserves tab state, conditional rendering does not.

// ✅ State preserved when hidden
Tab("Settings", systemImage: "gear") {
    SettingsView()  // Navigation stack preserved
}
.hidden(!showSettings)

// ❌ State lost when condition changes
if showSettings {
    Tab("Settings", systemImage: "gear") {
        SettingsView()  // Navigation stack recreated
    }
}

Common Patterns

Feature Flags

Tab("Beta Features", systemImage: "flask") {
    BetaView()
}
.hidden(!UserDefaults.standard.bool(forKey: "enableBetaFeatures"))

Authentication State

Tab("Profile", systemImage: "person.circle") {
    ProfileView()
}
.hidden(!authManager.isAuthenticated)

Purchase Status

Tab("Pro Features", systemImage: "star.circle.fill") {
    ProFeaturesView()
}
.hidden(!purchaseManager.isPro)

Development Builds

Tab("Debug", systemImage: "hammer") {
    DebugView()
}
.hidden(!isDevelopmentBuild)

private var isDevelopmentBuild: Bool {
    #if DEBUG
    return true
    #else
    return false
    #endif
}

Animated Transitions

Wrap state changes in withAnimation for smooth tab bar layout transitions:

Button("Switch to Browse") {
    withAnimation {
        context = .browse
        selection = .tracks  // Switch to first visible tab
    }
}
// Tab bar animates as tabs appear/disappear
// Uses system motion curves automatically

5.6 iOS 26+ Tab Features (WWDC 2025, 256)

// Tab bar minimization on scroll
TabView { ... }
    .tabBarMinimizeBehavior(.onScrollDown)

// Bottom accessory view (always visible)
TabView { ... }
    .tabViewBottomAccessory {
        PlaybackControls()
    }

// Dynamic visibility (recommended for mini-players)
// ⚠️ Requires iOS 26.1+ (not 26.0)
TabView { ... }
    .tabViewBottomAccessory(isEnabled: showMiniPlayer) {
        MiniPlayerView()
            .transition(.opacity)
    }
// isEnabled: true = shows accessory
// isEnabled: false = hides AND removes reserved space

// Search tab with dedicated search field
Tab(role: .search) {
    NavigationStack {
        SearchView()
            .navigationTitle("Search")
    }
    .searchable(text: $searchText)
}
// Morphs into search field when selected
// ⚠️ NavigationStack wrapper required for search field to appear
// Fallback: If no tab has .search role, the tab view applies search
// to ALL tabs, resetting search state when the selected tab changes

Dynamic Bottom Accessory

The accessory view can change based on the active tab, though Apple's own usage (Music mini-player) keeps it global:

@State private var activeTab: TabID = .workouts

TabView(selection: $activeTab) { /* tabs */ }
    .tabViewBottomAccessory {
        switch activeTab {
        case .workouts:
            Button("Start Workout") { }
        case .exercises:
            Button("Add Exercise") { }
        default:
            EmptyView()
        }
    }

Accessory placement: On iPhone, the bottom accessory position depends on tab bar state. When the tab bar is normal size, the accessory appears above it; when the tab bar is collapsed (via tabBarMinimizeBehavior), the accessory displays inline. Read the tabViewBottomAccessoryPlacement environment value to adjust content:

struct AdaptiveAccessory: View {
    @Environment(\.tabViewBottomAccessoryPlacement) var placement

    var body: some View {
        HStack {
            NowPlayingInfo()
            if placement == .bar {
                // Full controls when above tab bar
                PlaybackControls()
            } else {
                // Compact when inline with collapsed tab bar
                PlayPauseButton()
            }
        }
    }
}

Best practice: Reserve tabViewBottomAccessory for content relevant across all tabs (playback controls, status indicators). For tab-specific actions, prefer floating glass buttons within the tab's content view.

5.7 Tab API Quick Reference

iOS 26+ Navigation Features

6.1 Liquid Glass Navigation (WWDC 2025, 323)

Automatic adoption when building with Xcode 26:

• Navigation bars become Liquid Glass
• Sidebars float above content with glass effect
• Tab bars float with new compact appearance
• Toolbars get automatic grouping

6.2 Background Extension Effect

NavigationSplitView {
    Sidebar()
} detail: {
    HeroImage()
        .backgroundExtensionEffect()  // Content extends behind sidebar
}

6.3 Bottom-Aligned Search (WWDC 2025, 256)

Foundational search APIs For .searchable, isSearching, suggestions, scopes, tokens, and programmatic control, see axiom-swiftui-search-ref. This section covers iOS 26 bottom-aligned refinement only.

NavigationSplitView {
    Sidebar()
} detail: {
    DetailView()
}
.searchable(text: $query, prompt: "What are you looking for?")
// Automatically bottom-aligned on iPhone, top-trailing on iPad

6.4 Scroll Edge Effect

// Automatic blur effect when content scrolls under toolbar
// Remove any custom darkening backgrounds - they interfere

// For dense UIs, adjust sharpness
ScrollView { ... }
    .scrollEdgeEffectStyle(.soft)  // .sharp, .soft

6.5 Tab Bar Minimization

TabView {
    Tab("Home", systemImage: "house") {
        NavigationStack {
            ScrollView {
                // Content
            }
        }
    }
}
.tabBarMinimizeBehavior(.onScrollDown)  // Minimizes on scroll

6.6 Sheet Presentations with Zoom Transition

In iOS 26, sheets can morph directly out of the buttons that present them. Make the presenting toolbar item a source for a navigation zoom transition, and mark the sheet content as the destination:

@Namespace private var namespace

// Sheet morphs out of presenting button
.toolbar {
    ToolbarItem {
        Button("Settings") { showSettings = true }
            .matchedTransitionSource(id: "settings", in: namespace)
    }
}
.sheet(isPresented: $showSettings) {
    SettingsView()
        .navigationTransition(.zoom(sourceID: "settings", in: namespace))
}

Other presentations also flow smoothly out of Liquid Glass controls — menus, alerts, and popovers. Dialogs automatically morph out of the buttons that present them without additional code.

Audit tip: If you've used presentationBackground to apply custom backgrounds to sheets, consider removing it and let the new Liquid Glass sheet material shine. Partial height sheets are now inset with glass background by default.

6.7 Toolbar Morphing Transitions

iOS 26 automatically morphs toolbars during NavigationStack push/pop when each destination view declares its own .toolbar {}. Items with matching toolbar(id:) and ToolbarItem(id:) IDs stay stable during the transition (no bounce), while unmatched items animate in/out.

Key rule: Attach .toolbar {} to individual views inside NavigationStack, not to NavigationStack itself. Otherwise there is nothing to morph between.

See axiom-swiftui-26-ref skill for complete toolbar morphing API including DefaultToolbarItem, toolbar(id:) stable items, ToolbarSpacer patterns, and troubleshooting.

Router/Coordinator Patterns

7.1 When to Use Coordinators

Use coordinators when:

• Navigation logic is complex with conditional flows
• Testing navigation in isolation
• Sharing navigation logic across multiple screens
• UIKit interop with heavy navigation requirements

Use built-in navigation when:

• Simple linear or hierarchical navigation
• State restoration is primary concern
• Fewer than 5-10 navigation destinations
• No need for navigation unit testing

7.2 Simple Router Pattern

// Route enum defines all possible destinations
enum AppRoute: Hashable {
    case home
    case category(Category)
    case recipe(Recipe)
    case settings
}

// Router class manages navigation
@Observable
class Router {
    var path = NavigationPath()

    func navigate(to route: AppRoute) {
        path.append(route)
    }

    func popToRoot() {
        path.removeLast(path.count)
    }

    func pop() {
        if !path.isEmpty {
            path.removeLast()
        }
    }
}

// Usage in views
struct ContentView: View {
    @State private var router = Router()

    var body: some View {
        NavigationStack(path: $router.path) {
            HomeView()
                .navigationDestination(for: AppRoute.self) { route in
                    switch route {
                    case .home:
                        HomeView()
                    case .category(let category):
                        CategoryView(category: category)
                    case .recipe(let recipe):
                        RecipeDetail(recipe: recipe)
                    case .settings:
                        SettingsView()
                    }
                }
        }
        .environment(router)
    }
}

// In child views
struct RecipeCard: View {
    let recipe: Recipe
    @Environment(Router.self) private var router

    var body: some View {
        Button(recipe.name) {
            router.navigate(to: .recipe(recipe))
        }
    }
}

7.3 Coordinator Pattern with Protocol

protocol Coordinator {
    associatedtype Route: Hashable
    var path: NavigationPath { get set }
    func navigate(to route: Route)
}

@Observable
class RecipeCoordinator: Coordinator {
    typealias Route = RecipeRoute
    var path = NavigationPath()

    enum RecipeRoute: Hashable {
        case list(Category)
        case detail(Recipe)
        case edit(Recipe)
        case relatedRecipes(Recipe)
    }

    func navigate(to route: RecipeRoute) {
        path.append(route)
    }

    func showRecipeOfTheDay() {
        path.removeLast(path.count)
        if let recipe = DataModel.shared.recipeOfTheDay {
            path.append(RecipeRoute.detail(recipe))
        }
    }
}

7.4 Testing Navigation

// Router is easily testable
func testNavigateToRecipe() {
    let router = Router()
    let recipe = Recipe(name: "Apple Pie")

    router.navigate(to: .recipe(recipe))

    XCTAssertEqual(router.path.count, 1)
}

func testPopToRoot() {
    let router = Router()
    router.navigate(to: .category(.desserts))
    router.navigate(to: .recipe(Recipe(name: "Apple Pie")))

    router.popToRoot()

    XCTAssertTrue(router.path.isEmpty)
}

Testing Checklist

Navigation Flow Testing

• All NavigationLinks navigate to correct destination
• Back button returns to previous view
• Pop to root clears entire stack
• Deep links navigate correctly from cold start
• Deep links navigate correctly when app is running

State Restoration Testing

• Navigation state persists when app backgrounds
• Navigation state restores on app launch
• Deleted items handled gracefully (compactMap)
• SceneStorage key is unique per scene

Multi-Platform Testing

• NavigationSplitView collapses correctly on iPhone
• Selection in sidebar pushes on iPhone
• Tab bar visible and functional on all platforms
• Sidebar toggle works on iPad

iOS 26+ Testing

• Liquid Glass appearance correct
• Bottom-aligned search on iPhone
• Tab bar minimization works
• Scroll edge effect not interfering with custom backgrounds

API Quick Reference

NavigationStack

NavigationStack { content }
NavigationStack(path: $path) { content }

NavigationSplitView

NavigationSplitView { sidebar } detail: { detail }
NavigationSplitView { sidebar } content: { content } detail: { detail }
NavigationSplitView(columnVisibility: $visibility) { ... }

NavigationLink

NavigationLink(title, value: value)
NavigationLink(value: value) { label }

NavigationPath

path.append(value)
path.removeLast()
path.removeLast(path.count)
path.count
path.codable  // For encoding
NavigationPath(codableRepresentation)  // For decoding

Modifiers

.navigationTitle("Title")
.navigationDestination(for: Type.self) { value in View }
.searchable(text: $query)
.tabViewStyle(.sidebarAdaptable)
.tabBarMinimizeBehavior(.onScrollDown)
.backgroundExtensionEffect()

Resources

WWDC: 2022-10054, 2024-10147, 2025-256, 2025-323 (Build a SwiftUI app with the new design)

Docs: /swiftui/tabrole/search, /swiftui/view/tabbarminimizebehavior(_:), /swiftui/view/tabviewbottomaccessory(isenabled:content:)

Skills: axiom-swiftui-nav, axiom-swiftui-nav-diag, axiom-swiftui-26-ref, axiom-liquid-glass, axiom-swiftui-search-ref

Last Updated Based on WWDC 2022-10054, WWDC 2024-10147, WWDC 2025-256, WWDC 2025-323 (Build a SwiftUI app with the new design) Platforms iOS 16+, iPadOS 16+, macOS 13+, watchOS 9+, tvOS 16+