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This package uses the navigation APIs available in older SwiftUI versions (such asNavigationView andNavigationLink) to recreate the newNavigationStack APIs introduced in WWDC22, so that you can start targeting those APIs on older versions of iOS, tvOS, macOS and watchOS. When running on an OS version that supportsNavigationStack,NavigationStack will be used under the hood.

✅NavigationStack ->NBNavigationStack

✅NavigationLink ->NBNavigationLink

✅NavigationPath ->NBNavigationPath

✅navigationDestination ->nbNavigationDestination

✅NavigationPath.CodableRepresentation ->NBNavigationPath.CodableRepresentation

You can migrate to these APIs now, and when you eventually bump your deployment target, you can remove this library and easily migrate to its SwiftUI equivalent.NavigationStack's full API is replicated, so you can initialise anNBNavigationStack with a binding to anArray, with a binding to anNBNavigationPath binding, or with no binding at all.

import NavigationBackportimport SwiftUIstructContentView:View{@Statevarpath=NBNavigationPath()varbody:someView{NBNavigationStack(path: $path){HomeView().nbNavigationDestination(for:NumberList.self, destination:{ numberListinNumberListView(numberList: numberList)}).nbNavigationDestination(for:Int.self, destination:{ numberinNumberView(number: number)}).nbNavigationDestination(for:EmojiVisualisation.self, destination:{ visualisationinEmojiView(visualisation: visualisation)})}}}structHomeView:View{varbody:someView{VStack(spacing:8){NBNavigationLink(value:NumberList(range:0..<100), label:{Text("Pick a number")})}.navigationTitle("Home")}}structNumberList:Hashable{letrange:Range<Int>}structNumberListView:View{letnumberList:NumberListvarbody:someView{List{ForEach(numberList.range, id: \.self){ numberinNBNavigationLink("\(number)", value: number)}}.navigationTitle("List")}}structNumberView:View{@EnvironmentObjectvarnavigator:PathNavigatorletnumber:Intvarbody:someView{VStack(spacing:8){Text("\(number)")NBNavigationLink(        value: number+1,        label:{Text("Show next number")})NBNavigationLink(        value:EmojiVisualisation(emoji:"🐑", count: number),        label:{Text("Visualise with sheep")})Button("Go back to root", action:{ navigator.popToRoot()})}.navigationTitle("\(number)")}}structEmojiVisualisation:Hashable{letemoji:Stringletcount:Intvartext:String{Array(repeating: emoji, count: count).joined()}}structEmojiView:View{letvisualisation:EmojiVisualisationvarbody:someView{Text(visualisation.text).navigationTitle("Visualise\(visualisation.count)")}}

As well as replicating the standard features of the newNavigationStack APIs, some helpful utilities have also been added.

ANavigator object is available through the environment, giving access to the current navigation path. The navigator can be accessed via the environment, e.g. for a NBNavigationPath-backed stack:

@EnvironmentObjectvarnavigator:PathNavigator

Or for a stack backed by an Array, e.g.[ScreenType]:

@EnvironmentObjectvarnavigator:Navigator<ScreenType>

As well as allowing you to inspect the path elements, the navigator can be used to push new screens, pop, pop to a specific screen or pop to the root.

Whether interacting with anArray, anNBNavigationPath, or aNavigator, a number of utility functions are available for easier navigation, such as:

path.push(Profile(name:"John"))path.pop()path.popToRoot()path.popTo(Profile.self)

Note that, if you want to use these methods on anArray, ensure theArray'sElement conforms toNBScreen, a protocol that inherits from Hashable without adding any additional requirements. This avoids polluting all arrays with APIs specific to navigation.

BeforeNavigationStack, SwiftUI did not support pushing more than one screen in a single state update, e.g. when deep-linking to a screen multiple layers deep in a navigation hierarchy.NavigationBackport works around this limitation: you can make any such path changes, and the library will, behind the scenes, break down the larger update into a series of smaller updates that SwiftUI supports if necessary, with delays in between. For example, the following code that pushes three screens in one state update will push the screens one by one if needed:

  path.append(Screen.orders)  path.append(Screen.editOrder(id: id))  path.append(Screen.confirmChanges(orderId: id))

This only happens when necessary: on versions of SwiftUI that supportNavigationStack, all three screens will be pushed successfully in one update.

This library targets iOS/tvOS versions 14 and above, since it usesStateObject, which is unavailable on iOS/tvOS 13. However, there is anios13 branch, which usesSwiftUIBackports' backported StateObject, so that it works on iOS/tvOS 13 too.