TitleBar 中的 SwiftUI NavigationLink 两次推送视图，一个 Button 做同样的事情不是

Question

这很烦人。 NavigationBar 中的 Edit 按钮推动 View 两次。我做了一个测试按钮，它的行为正确地做同样的事情：

import SwiftUI

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

var listName: ListNames

//    @State private var isEditDetailListPageShowing = false
@State private var selection: String? = nil

var body: some View {
    Form {
        Section(header: Text(listName.title ?? "")
                    .font(.title)
                    .padding()) {

            Text(listName.listDetail ?? "Nothing is set yet!")
                .multilineTextAlignment(.leading)
                .padding()
                .cornerRadius(12)
        }
        NavigationLink(destination: EditDetailListPage(listName: listName)) {
            Button {
                
            } label: {
                Text("Edit Page")
            }
        }
    }
    .navigationBarBackButtonHidden(true)
    
    .toolbar {
        ToolbarItem(placement: .navigationBarTrailing) {
            Button {
                self.presentationMode.wrappedValue.dismiss()
            } label: {
                Text("Cancel")
            } .padding()
            //Edit List Detail
        }
        ToolbarItem(placement: .navigationBarTrailing) {
            NavigationLink(
                destination: EditDetailListPage(listName: listName)) {
                Text("Edit")
            }

    }
    
}
}

上面的 Text("Edit") 将视图推送两次。 它上面的 Button 动作正确。想使用导航条而不是按钮。

Answer 1

适用于我，在 macos 11.4、xcode 12.5、目标 ios 14.5 和 macCatalyst 11.3 上。 可能是导致问题的其他代码（或设置/系统）。 你用的是什么系统？向我们展示缺少的代码以及如何调用视图。如果下面的测试代码不适合您，请告诉我们。

这是我使用的测试代码：

@main
struct TestErrorApp: App {
    var body: some Scene {
        WindowGroup {
            ContentView()
        }
    }
}
struct EditDetailListPage: View {
    var listName: [String]
    var body: some View {
        Text("EditDetailListPage")
    }
}

struct ContentView: View {
    var body: some View {
        NavigationView {
            DetailListPage(listName: ["test var"])
        }.navigationViewStyle(StackNavigationViewStyle())
    }
}

struct DetailListPage: View {
    @Environment(\.presentationMode) var presentationMode
    var listName: [String]
    //  @State private var isEditDetailListPageShowing = false
    @State private var selection: String? = nil
    
    var body: some View {
        Form {
            Section(header: Text("header string")
                        .font(.title)
                        .padding()) {
                Text("Nothing is set yet!")
                    .multilineTextAlignment(.leading)
                    .padding()
                    .cornerRadius(12)
            }
            NavigationLink(destination: EditDetailListPage(listName: listName)) {
                Button {
                } label: {
                    Text("Edit Page")
                }
            }
        }
        .navigationBarBackButtonHidden(true)
        .toolbar {
            ToolbarItem(placement: .navigationBarTrailing) {
                Button {
                    self.presentationMode.wrappedValue.dismiss()
                } label: {
                    Text("Cancel")
                } .padding()
                //Edit List Detail
            }
            ToolbarItem(placement: .navigationBarTrailing) {
                NavigationLink(
                    destination: EditDetailListPage(listName: listName)) {
                    Text("Edit")
                }
            }
        }
    }
}

struct ListFrontPage: View {
    
    @Environment(\.presentationMode) var presentationMode
    @Environment(\.managedObjectContext) var managedObjectContext
    
    @State private var isAddNewListShowing = false
    
    var listNames: FetchRequest<ListNames>

    init() {
        listNames = FetchRequest<ListNames>(entity: ListNames.entity(), sortDescriptors: [NSSortDescriptor(keyPath: \ListNames.sort, ascending: true)], animation: .default)
    }
    
    var body: some View {
        VStack {
            List() {
                Text("Accounts")
                    .frame(maxWidth: .infinity)
                    .font(.system(size: 30, weight: .heavy, design: .default))
                ForEach (listNames.wrappedValue) { listName in
                    NavigationLink(destination: DetailListPage(listName: listName)) {
                        Text("\(listName.title ?? "")")
                    }
                }
                .onDelete(perform: deleteItems)
                .onMove(perform: moveItem)
            }
            Spacer()
            ZStack {
                NavigationLink(destination: AddNewList()) {
                    Image(systemName: "plus.circle.fill").font(.system(size: 64))
                }
            }
        }
        .navigationBarBackButtonHidden(true)
        .navigationBarItems(leading: Button {
            self.presentationMode.wrappedValue.dismiss()
        } label: {
            Image(systemName: "chevron.backward")
            Label("Back", image: "")
        }, trailing: EditButton())
        .navigationBarTitle(Text("Account Management"))
    }
    
    private func deleteItems(offsets: IndexSet) {
        withAnimation {
            offsets.map { listNames.wrappedValue[$0] }.forEach(CoreDataHelper.sharedManager.deleteItems)
            
        }
    }
    
    private func moveItem(from offsets: IndexSet, to destination: Int)
    {
        print("From: \(String(describing: offsets)) To: \(destination)")
        // Make an array of items from fetched results
        var revisedItems: [ ListNames ] = listNames.wrappedValue.map{ $0 }
        
        // change the order of the items in the array
        revisedItems.move(fromOffsets: offsets, toOffset: destination )
                
        // update the userOrder attribute in revisedItems to
        // persist the new order. This is done in reverse order
        // to minimize changes to the indices.
        for reverseIndex in stride( from: revisedItems.count - 1,
                                    through: 0,
                                    by: -1 )
        {
            revisedItems[ reverseIndex ].sort =
                Int16( reverseIndex )
        }
    }
}