swiftui-navigation（swiftui navigation 搜索）

SwiftUI Navigation

Navigation patterns for SwiftUI apps targeting iOS 26+ with Swift 6.3. Covers push navigation, multi-column layouts, sheet presentation, tab architecture, and deep linking. Patterns are backward-compatible to iOS 17 unless noted.

Contents

• NavigationStack (Push Navigation)
• NavigationSplitView (Multi-Column)
• Sheet Presentation
• Tab-Based Navigation
• Deep Links
• Common Mistakes
• Review Checklist
• References

NavigationStack (Push Navigation)

Use NavigationStack with a NavigationPath binding for programmatic, type-safe push navigation. Define routes as a Hashable enum and map them with .navigationDestination(for:).

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

    var body: some View {
        NavigationStack(path: $path) {
            List(items) { item in
                NavigationLink(value: item) {
                    ItemRow(item: item)
                }
            }
            .navigationDestination(for: Item.self) { item in
                DetailView(item: item)
            }
            .navigationTitle("Items")
        }
    }
}

Programmatic navigation:

path.append(item)        // Push
path.removeLast()        // Pop one
path = NavigationPath()  // Pop to root

Router pattern: For apps with complex navigation, use a router object that owns the path and sheet state. Each tab gets its own router instance injected via .environment(). Centralize destination mapping with a single .navigationDestination(for:) block or a shared withAppRouter() modifier.

See references/navigationstack.md for full router examples including per-tab stacks, centralized destination mapping, and generic tab routing.

NavigationSplitView (Multi-Column)

Use NavigationSplitView for sidebar-detail layouts on iPad and Mac. Falls back to stack navigation on iPhone.

struct MasterDetailView: View {
    @State private var selectedItem: Item?

    var body: some View {
        NavigationSplitView {
            List(items, selection: $selectedItem) { item in
                NavigationLink(value: item) { ItemRow(item: item) }
            }
            .navigationTitle("Items")
        } detail: {
            if let item = selectedItem {
                ItemDetailView(item: item)
            } else {
                ContentUnavailableView("Select an Item", systemImage: "sidebar.leading")
            }
        }
    }
}

Custom Split Column (Manual HStack)

For custom multi-column layouts (e.g., a dedicated notification column independent of selection), use a manual HStack split with horizontalSizeClass checks:

@MainActor
struct AppView: View {
  @Environment(\.horizontalSizeClass) private var horizontalSizeClass
  @AppStorage("showSecondaryColumn") private var showSecondaryColumn = true

  var body: some View {
    HStack(spacing: 0) {
      primaryColumn
      if shouldShowSecondaryColumn {
        Divider().edgesIgnoringSafeArea(.all)
        secondaryColumn
      }
    }
  }

  private var shouldShowSecondaryColumn: Bool {
    horizontalSizeClass == .regular
      && showSecondaryColumn
  }

  private var primaryColumn: some View {
    TabView { /* tabs */ }
  }

  private var secondaryColumn: some View {
    NotificationsTab()
      .environment(\.isSecondaryColumn, true)
      .frame(maxWidth: .secondaryColumnWidth)
  }
}

Use the manual HStack split when you need full control or a non-standard secondary column. Use NavigationSplitView when you want a standard system layout with minimal customization.

Sheet Presentation

Prefer .sheet(item:) over .sheet(isPresented:) when state represents a selected model. Sheets should own their actions and call dismiss() internally.

@State private var selectedItem: Item?

.sheet(item: $selectedItem) { item in
    EditItemSheet(item: item)
}

Presentation sizing (iOS 18+): Control sheet dimensions with .presentationSizing:

.sheet(item: $selectedItem) { item in
    EditItemSheet(item: item)
        .presentationSizing(.form)  // .form, .page, .fitted, .automatic
}

PresentationSizing values:

• .automatic -- platform default
• .page -- roughly paper size, for informational content
• .form -- slightly narrower than page, for form-style UI
• .fitted -- sized by the content's ideal size

Fine-tuning: .fitted(horizontal:vertical:) constrains fitting axes; .sticky(horizontal:vertical:) grows but does not shrink in specified dimensions.

Dismissal confirmation (macOS 15+ / iOS 26+): Use .dismissalConfirmationDialog("Discard?", shouldPresent: hasUnsavedChanges) to prevent accidental dismissal of sheets with unsaved changes.

Enum-driven sheet routing: Define a SheetDestination enum that is Identifiable, store it on the router, and map it with a shared view modifier. This lets any child view present sheets without prop-drilling. See references/sheets.md for the full centralized sheet routing pattern.

Tab-Based Navigation

Use the Tab API with a selection binding for scalable tab architecture. Each tab should wrap its content in an independent NavigationStack.

struct MainTabView: View {
    @State private var selectedTab: AppTab = .home

    var body: some View {
        TabView(selection: $selectedTab) {
            Tab("Home", systemImage: "house", value: .home) {
                NavigationStack { HomeView() }
            }
            Tab("Search", systemImage: "magnifyingglass", value: .search) {
                NavigationStack { SearchView() }
            }
            Tab("Profile", systemImage: "person", value: .profile) {
                NavigationStack { ProfileView() }
            }
        }
    }
}

Custom binding with side effects: Route selection changes through a function to intercept special tabs (e.g., compose) that should trigger an action instead of changing selection.

iOS 26 Tab Additions

• Tab(role:.search) -- replaces the tab bar with a search field when active
• .tabBarMinimizeBehavior(_:) -- .onScrollDown, .onScrollUp, .never (iPhone only)
• .tabViewSidebarHeader/Footer -- customize sidebar sections on iPadOS/macOS
• .tabViewBottomAccessory {} -- attach content below the tab bar (e.g., Now Playing bar)
• TabSection -- group tabs into sidebar sections with .tabPlacement(.sidebarOnly)

See references/tabview.md for full TabView patterns including custom bindings, dynamic tabs, and sidebar customization.

Deep Links

Universal Links

Universal links let iOS open your app for standard HTTPS URLs. They require:

1. An Apple App Site Association (AASA) file at /.well-known/apple-app-site-association
2. An Associated Domains entitlement (applinks:example.com)

Handle in SwiftUI with .onOpenURL and .onContinueUserActivity:

@main
struct MyApp: App {
    @State private var router = Router()

    var body: some Scene {
        WindowGroup {
            ContentView()
                .environment(router)
                .onOpenURL { url in router.handle(url: url) }
                .onContinueUserActivity(NSUserActivityTypeBrowsingWeb) { activity in
                    guard let url = activity.webpageURL else { return }
                    router.handle(url: url)
                }
        }
    }
}

Custom URL Schemes

Register schemes in Info.plist under CFBundleURLTypes. Handle with .onOpenURL. Prefer universal links over custom schemes for publicly shared links -- they provide web fallback and domain verification.

Handoff (NSUserActivity)

Advertise activities with .userActivity() and receive them with .onContinueUserActivity(). Declare activity types in Info.plist under NSUserActivityTypes. Set isEligibleForHandoff = true and provide a webpageURL as fallback.

See references/deeplinks.md for full examples of AASA configuration, router URL handling, custom URL schemes, and NSUserActivity continuation.

Common Mistakes

1. Using deprecated NavigationView -- use NavigationStack or NavigationSplitView
2. Sharing one NavigationPath across all tabs -- each tab needs its own path
3. Using .sheet(isPresented:) when state represents a model -- use .sheet(item:) instead
4. Storing view instances in NavigationPath -- store lightweight Hashable route data
5. Nesting @Observable router objects inside other @Observable objects
6. Prefer Tab(value:) with TabView(selection:) over the older .tabItem {} API
7. Assuming tabBarMinimizeBehavior works on iPad -- it is iPhone only
8. Handling deep links in multiple places -- centralize URL parsing in the router
9. Hard-coding sheet frame dimensions -- use .presentationSizing(.form) instead
10. Missing @MainActor on router classes -- required for Swift 6 concurrency safety

Review Checklist

• NavigationStack used (not NavigationView)
• Each tab has its own NavigationStack with independent path
• Route enum is Hashable with stable identifiers
• .navigationDestination(for:) maps all route types
• .sheet(item:) preferred over .sheet(isPresented:)
• Sheets own their dismiss logic internally
• Router object is @MainActor and @Observable
• Deep link URLs parsed and validated before navigation
• Universal links have AASA and Associated Domains configured
• Tab selection uses Tab(value:) with binding

References

• NavigationStack and router patterns: references/navigationstack.md
• Sheet presentation and routing: references/sheets.md
• TabView patterns and iOS 26 API: references/tabview.md
• Deep links, universal links, and Handoff: references/deeplinks.md
• Architecture and state management: see swiftui-patterns skill
• Layout and components: see swiftui-layout-components skill