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Custom back button for NavigationView's navigation bar in SwiftUI

I want to add a custom navigation button that will look somewhat like this:

所需的导航返回按钮

Now, I've written a custom BackButton view for this. When applying that view as leading navigation bar item, by doing:

.navigationBarItems(leading: BackButton())

...the navigation view looks like this:

当前导航返回按钮

I've played around with modifiers like:

.navigationBarItem(title: Text(""), titleDisplayMode: .automatic, hidesBackButton: true)

without any luck.

Question

How can I...

  1. set a view used as custom back button in the navigation bar? OR:
  2. programmatically pop the view back to its parent?
    When going for this approach, I could hide the navigation bar altogether using .navigationBarHidden(true)

TL;DR

Use this to transition to your view:

NavigationLink(destination: SampleDetails()) {}

Add this to the view itself:

@Environment(\.presentationMode) var presentationMode: Binding<PresentationMode>

Then, in a button action or something, dismiss the view:

presentationMode.wrappedValue.dismiss()

Full code

From a parent, navigate using NavigationLink

 NavigationLink(destination: SampleDetails()) {}

In DetailsView hide navigationBarBackButton and set custom back button to leading navigationBarItem ,

struct SampleDetails: View {
    @Environment(\.presentationMode) var presentationMode: Binding<PresentationMode>

    var btnBack : some View { Button(action: {
        self.presentationMode.wrappedValue.dismiss()
        }) {
            HStack {
            Image("ic_back") // set image here
                .aspectRatio(contentMode: .fit)
                .foregroundColor(.white)
                Text("Go back")
            }
        }
    }
    
    var body: some View {
            List {
                Text("sample code")
        }
        .navigationBarBackButtonHidden(true)
        .navigationBarItems(leading: btnBack)
    }
}

SwiftUI 1.0

It looks like you can now combine the navigationBarBackButtonHidden and .navigationBarItems to get the effect you're trying to achieve.

Code

struct Navigation_CustomBackButton_Detail: View {
    @Environment(\.presentationMode) var presentationMode
    
    var body: some View {
        ZStack {
            Color("Theme3BackgroundColor")
            VStack(spacing: 25) {
                Image(systemName: "globe").font(.largeTitle)
                Text("NavigationView").font(.largeTitle)
                Text("Custom Back Button").foregroundColor(.gray)
                HStack {
                    Image("NavBarBackButtonHidden")
                    Image(systemName: "plus")
                    Image("NavBarItems")
                }
                Text("Hide the system back button and then use the navigation bar items modifier to add your own.")
                    .frame(maxWidth: .infinity)
                    .padding()
                    .background(Color("Theme3ForegroundColor"))
                    .foregroundColor(Color("Theme3BackgroundColor"))
                
                Spacer()
            }
            .font(.title)
            .padding(.top, 50)
        }
        .navigationBarTitle(Text("Detail View"), displayMode: .inline)
        .edgesIgnoringSafeArea(.bottom)
        // Hide the system back button
        .navigationBarBackButtonHidden(true)
        // Add your custom back button here
        .navigationBarItems(leading:
            Button(action: {
                self.presentationMode.wrappedValue.dismiss()
            }) {
                HStack {
                    Image(systemName: "arrow.left.circle")
                    Text("Go Back")
                }
        })
    }
}

Example

Here is what it looks like (excerpt from the "SwiftUI Views" book): SwiftUI 视图书摘

Based on other answers here, this is a simplified answer for Option 2 working for me in XCode 11.0:

struct DetailView: View {
    @Environment(\.presentationMode) var presentationMode: Binding<PresentationMode>

    var body: some View {

        Button(action: {
           self.presentationMode.wrappedValue.dismiss()
        }) {
            Image(systemName: "gobackward").padding()
        }
        .navigationBarHidden(true)

    }
}

Note: To get the NavigationBar to be hidden, I also needed to set and then hide the NavigationBar in ContentView.

struct ContentView: View {
    var body: some View {
        NavigationView {
            VStack {
                NavigationLink(destination: DetailView()) {
                    Text("Link").padding()
                }
            } // Main VStack
            .navigationBarTitle("Home")
            .navigationBarHidden(true)

        } //NavigationView
    }
}

Here's a more condensed version using principles shown in the other comments to change only the text of the button. The chevron.left icon can also be easily replaced with another icon.

Create your own button, then assign it using .navigationBarItems(). I found the following format most nearly approximated the default back button.

    @Environment(\.presentationMode) var presentationMode: Binding<PresentationMode>

    var backButton : some View {
        Button(action: {
            self.presentationMode.wrappedValue.dismiss()
        }) {
            HStack(spacing: 0) {
                Image(systemName: "chevron.left")
                    .font(.title2)
                Text("Cancel")
            }
        }
    }

Make sure you use .navigationBarBackButtonHidden(true) to hide the default button and replace it with your own!

        List(series, id:\.self, selection: $selection) { series in
            Text(series.SeriesLabel)
        }
        .navigationBarBackButtonHidden(true)
        .navigationBarItems(leading: backButton)

I expect you want to use custom back button in all navigable screens, so I wrote custom wrapper based on @Ashish answer.

struct NavigationItemContainer<Content>: View where Content: View {
    private let content: () -> Content
    @Environment(\.presentationMode) var presentationMode

    private var btnBack : some View { Button(action: {
        self.presentationMode.wrappedValue.dismiss()
    }) {
        HStack {
            Image("back_icon") // set image here
                .aspectRatio(contentMode: .fit)
                .foregroundColor(.black)
            Text("Go back")
        }
        }
    }

    var body: some View {
        content()
            .navigationBarBackButtonHidden(true)
            .navigationBarItems(leading: btnBack)
    }

    init(@ViewBuilder content: @escaping () -> Content) {
        self.content = content
    }
}

Wrap screen content in NavigationItemContainer:

Usage:

struct CreateAccountScreenView: View {
    var body: some View {
        NavigationItemContainer {
            VStack(spacing: 21) {
                AppLogoView()
                //...
            }
        }
    }
}

Swiping is not disabled this way.

Works for me. XCode 11.3.1

Put this in your root View

init() {
    UINavigationBar.appearance().isUserInteractionEnabled = false
    UINavigationBar.appearance().backgroundColor = .clear
    UINavigationBar.appearance().barTintColor = .clear
    UINavigationBar.appearance().setBackgroundImage(UIImage(), for: .default)
    UINavigationBar.appearance().shadowImage = UIImage()
    UINavigationBar.appearance().tintColor = .clear
}

And this in your child View

@Environment(\.presentationMode) var presentationMode: Binding<PresentationMode>

Button(action: {self.presentationMode.wrappedValue.dismiss()}) {
    Image(systemName: "gobackward")
}

You can use UIAppearance for this:

if let image = UIImage(named: "back-button") {
    UINavigationBar.appearance().backIndicatorImage = image
    UINavigationBar.appearance().backIndicatorTransitionMaskImage = image
}

This should be added early on in your app like App.init . This also preserves the native swipe back functionality.

All of the solutions I see here seem to disable swipe to go back functionality to navigate to the previous page, so sharing a solution I found that maintains that functionality. You can make an extension of your root view and override your navigation style and call the function in the view initializer.

Sample View

struct SampleRootView: View {

    init() {
        overrideNavigationAppearance()
    }

    var body: some View {
        Text("Hello, World!")
    }
}

Extension

extension SampleRootView {
   func overrideNavigationAppearance() {
        let navigationBarAppearance = UINavigationBarAppearance()
        let barAppearace = UINavigationBar.appearance()
        barAppearace.tintColor = *desired UIColor for icon*
        barAppearace.barTintColor = *desired UIColor for icon*

        navigationBarAppearance.setBackIndicatorImage(*desired UIImage for custom icon*, transitionMaskImage: *desired UIImage for custom icon*)

        UINavigationBar.appearance().standardAppearance = navigationBarAppearance
        UINavigationBar.appearance().compactAppearance = navigationBarAppearance
        UINavigationBar.appearance().scrollEdgeAppearance = navigationBarAppearance
   }
}

The only downfall to this approach is I haven't found a way to remove/change the text associated with the custom back button.

This solution works for iPhone. However, for iPad it won't work because of the splitView.

import SwiftUI

struct NavigationBackButton: View {
  var title: Text?
  @Environment(\.presentationMode) private var presentationMode: Binding<PresentationMode>

  var body: some View {
    ZStack {
      VStack {
        ZStack {
          HStack {
            Button(action: {
              self.presentationMode.wrappedValue.dismiss()
            }) {
              Image(systemName: "chevron.left")
                .font(.title)
                .frame(width: 44, height: 44)
              title
            }
            Spacer()
          }
        }
        Spacer()
      }
    }
    .zIndex(1)
    .navigationBarTitle("")
    .navigationBarHidden(true)
  }
}

struct NavigationBackButton_Previews: PreviewProvider {
  static var previews: some View {
    NavigationBackButton()
  }
}

Really simple method. Only two lines code 🔥

@Environment(\.presentationMode) var presentationMode
self.presentationMode.wrappedValue.dismiss()

Example:

import SwiftUI

struct FirstView: View {
    @State var showSecondView = false
    
    var body: some View {
        NavigationLink(destination: SecondView(),isActive : self.$showSecondView){
            Text("Push to Second View")
        }
    }
}


struct SecondView : View{
    @Environment(\.presentationMode) var presentationMode

    var body : some View {    
        Button(action:{ self.presentationMode.wrappedValue.dismiss() }){
            Text("Go Back")    
        }    
    }
}

I found this: https://ryanashcraft.me/swiftui-programmatic-navigation/

It does work, and it may lay the foundation for a state machine to control what is showing, but it is not a simple as it was before.

import Combine
import SwiftUI

struct DetailView: View {
    var onDismiss: () -> Void

    var body: some View {
        Button(
            "Here are details. Tap to go back.",
            action: self.onDismiss
        )
    }
}

struct RootView: View {
    var link: NavigationDestinationLink<DetailView>
    var publisher: AnyPublisher<Void, Never>

    init() {
        let publisher = PassthroughSubject<Void, Never>()
        self.link = NavigationDestinationLink(
            DetailView(onDismiss: { publisher.send() }),
            isDetail: false
        )
        self.publisher = publisher.eraseToAnyPublisher()
    }

    var body: some View {
        VStack {
            Button("I am root. Tap for more details.", action: {
                self.link.presented?.value = true
            })
        }
            .onReceive(publisher, perform: { _ in
                self.link.presented?.value = false
            })
    }
}

struct ContentView: View {
    var body: some View {
        NavigationView {
            RootView()
        }
    }
}

If you want to hide the button then you can replace the DetailView with this:

struct LocalDetailView: View {
    var onDismiss: () -> Void

    var body: some View {
        Button(
            "Here are details. Tap to go back.",
            action: self.onDismiss
        )
            .navigationBarItems(leading: Text(""))
    }
}

Just write this:

import SwiftUI

struct ContentView: View {
    var body: some View {
        NavigationView {

        }.onAppear() {
            UINavigationBar.appearance().tintColor = .clear
            UINavigationBar.appearance().backIndicatorImage = UIImage(named: "back")?.withRenderingMode(.alwaysOriginal)
            UINavigationBar.appearance().backIndicatorTransitionMaskImage = UIImage(named: "back")?.withRenderingMode(.alwaysOriginal)
        }
    }
}

On iOS 14+ it's actually very easy using presentationMode variable

In this example NewItemView will get dismissed on addItem completion:

struct NewItemView: View {
    @State private var itemDescription:String = ""
    @Environment(\.presentationMode) var presentationMode: Binding<PresentationMode>
    
    
    var body: some View {
        VStack {
            TextEditor(text: $itemDescription)
        }.onTapGesture {
            hideKeyboard()
        }.toolbar {
            
            ToolbarItem {
                Button(action: addItem){
                    Text("Save")
                }
            }
            
        }.navigationTitle("Add Question")
        
    }
    private func addItem() {
        // Add save logic
        // ...
        
        // Dismiss on complete
        presentationMode.wrappedValue.dismiss()
    }
    
    private func hideKeyboard() {
        UIApplication.shared.sendAction(#selector(UIResponder.resignFirstResponder), to: nil, from: nil, for: nil)
    }
}

struct NewItemView_Previews: PreviewProvider {
    static var previews: some View {
        NewItemView()
    }
}

In case you need the parent (Main) view:

struct SampleMainView: View {
    @Environment(\.managedObjectContext) private var viewContext
    @FetchRequest(
        sortDescriptors: [NSSortDescriptor(keyPath: \DbQuestion.timestamp, ascending: true)],
        animation: .default)
    private var items: FetchedResults<Item>
    
    var body: some View {
        NavigationView {
            List {
                ForEach(items) { item in
                    NavigationLink {
                        Text("This is item detail page")
                    } label: {
                        Text("Item at \(item.id)")
                    }
                }
                
            }
            .toolbar {
                ToolbarItem {
                        // Creates a button on toolbar
                        NavigationLink {
                            // New Item Page
                            NewItemView()
                        } label: {
                            Text("Add item")
                        }
                }
                ToolbarItem(placement: .navigationBarTrailing) {
                    EditButton()
                }
            }.navigationTitle("Main Screen")
            
        }
    }
}

iOS 15

presentationMode.wrappedValue.dismiss() is now deprecated.

It's replaced by DismissAction

private struct SheetContents: View {
    @Environment(\.dismiss) private var dismiss

    var body: some View {
        Button("Done") {
            dismiss()
        }
    }
}

You still create the custom back button the same way.

struct NavBackButton: View {
    let dismiss: DismissAction
    
    var body: some View {
        Button {
            dismiss()
        } label: {
            Image("...custom back button here")
        }
    }
}

Attach it to your view.

.navigationBarBackButtonHidden(true) // Hide default button
.navigationBarItems(leading: NavBackButton(dismiss: self.dismiss)) // Attach custom button

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