SOLVED: How to pass a variable backwards and forward between views?

@ZebsZebs

Apr '22

The title isn't very clear but this is what I want to do:

ForEach(tortoises.items, id: \.name){ item in
                                VStack{
                                    Text("Name: \(item.name)")
                                        .font(.title)
                                    Text("Age: \(item.age)")
                                        .font(.title)
                                    NavigationLink("Change Age"){
                                        AgeChange(age: item.age) 

                                    }

I want to change item.age using this picker in a different view

Here is the view:


struct AgeChange: View{
    @State var age: Int
    var body: some View{
        Picker("Age:", selection: $age){
            ForEach(0..<120){
                Text("Age: \($0)")
                    .font(.title)

            }
        }
    }
}

@Hatsushira HWS+

Apr '22

This is because in your AgeChange you declared age as @State. Basically, it means, that your age variable is owned by this view. Which is not. You need a Binding.

https://www.hackingwithswift.com/quick-start/swiftui/what-is-the-binding-property-wrapper

I changed your variable name just to create my own examples.

NavigationView {
    List($myTortoises, id: \.name) { $item in
    VStack{
        Text(item.name)
        .font(.title)
      Text("Age: \(item.age)")
          .font(.title)
            NavigationLink("Change Age"){
        AgeChange(age: $item.age)                
            }
        }
    }
}

struct AgeChange: View{
    @Binding var age: Int

    var body: some View{
    Picker("Age:", selection: $age){
        ForEach(0..<120){
        Text("Age: \($0)")
            .font(.title)
      }
    }
  }
}

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