SwiftUI NavigationLink pops out by itself

Question

I have a simple use case where a screen pushes another screen using the NavigationLink. There is a strange behaviour iOS 14.5 beta where the pushed screen is popped just after being pushed.

I manage to create a sample app where I reproduce it. I believe the cause is the presence of @Environment(\.presentationMode) that seem to re-create the view and it causes the pushed view to be popped.

The exact same code works fine in Xcode 12 / iOS 14.4

Here is a sample code.

Code Block swiftimport SwiftUI
public struct FirstScreen: View {
  public init() {}
  public var body: some View {
    NavigationView {
      List {
        row
        row
        row
      }
    }
  }
  private var row: some View {
    NavigationLink(destination: SecondScreen()) {
      Text("Row")
    }
  }
}
struct SecondScreen: View {
  @Environment(\.presentationMode) var presentationMode: Binding<PresentationMode>
  public var body: some View {
    VStack(spacing: 10) {
      NavigationLink(destination: thirdScreenA) {
        Text("Link to Third Screen A")
      }
      NavigationLink(destination: thirdScreenB) {
        Text("Link to Third Screen B")
      }
      Button("Go back", action: { presentationMode.wrappedValue.dismiss() })
    }
  }
  var thirdScreenA: some View {
    Text("thirdScreenA")
  }
  var thirdScreenB: some View {
    Text("thirdScreenB")
  }
}
struct FirstScreen_Previews: PreviewProvider {
  static var previews: some View {
    FirstScreen()
  }
}

SwiftUI

51k

Posted by

JanC

Reply

The WA works. But this is still present in 14.7.

—
Orhan_swe

Code Block
NavigationLink(destination: EmptyView()) {
EmptyView()
}

Code Block Swift
struct NavigationLazyView<Content: View>: View {
let build: () -> Content
init(_ build: @autoclosure @escaping () -> Content) {
self.build = build
}
var body: Content {
build()
}
}

NavigationLink(destination: NavigationLazyView(DetailView())) { Text("Click me") }

Code Block swift
extension View {
func navigate<Destination: View>(
isActive: Binding<Bool>,
destination: Destination?
) -> some View {
background(
NavigationLink(
destination: destination,
isActive: isActive,
label: EmptyView.init
)
.hidden()
)
}
}

extension View {
func navigate<Item, Destination: View>(
item: Binding<Item?>,
destination: (Item) -> Destination
) -> some View {
navigate(
isActive: Binding(
get: { item.wrappedValue != nil },
set: { if !$0 { item.wrappedValue = nil } }
),
destination: Group {
if let item = item.wrappedValue {
destination(item)
}
}
)
}
}

Code Block swift
struct ShowMoreView: View {
@State private var isLinkActive = false

var body: some View {
List {
Button(action: { isLinkActive = true })
Text("Start navigation 1")
}
Button(action: { isLinkActive = true })
Text("Start navigation 2")
}
Button(action: { isLinkActive = true })
Text("Start navigation 3")
}
}
.navigate(isActive: $isLinkActive, destination: makeDestination())
}
}

struct ShowMoreView: View {
@State private var date: Date?

var body: some View {
List {
Button(action: { date = Date() })
Text("Start navigation 1")
}
Button(action: { date = Date() + 100 })
Text("Start navigation 2")
}
Button(action: { date = Date() + 1000 })
Text("Start navigation 3")
}
}
.navigate(item: $date, destination: makeDestination)
}

func makeDestination(for date: Date) -> some View {
...
}

SwiftUI NavigationLink pops out by itself

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