Picker Row not getting deselected in Form (SwiftUI, Xcode 12 beta 4)

Question

I am creating a picker in a form in SwiftUI. On selection of a new element in picker, when the view pulls back to the form, the picker row isn't getting deselected. Here is a screenshot of what I mean, the picker row remains grayed out like this.

I read some previous answers which say that this was a bug in Xcode 11.3, however, I'm running Xcode 12 beta 4 and am not sure if this is still a bug.

This is how I'm creating the picker:

struct SettingsView: View {
    @State private var currentSelection = 1
    var body: some View {
        NavigationView {
            Form {
                Section {
                    Picker("Test 2", selection: $currentSelection) {
                        ForEach(1 ...< 100) { i in
                            Text(String(i)).tag(i)
                        }
                    }
                }
            }
        }
    }
}

Here is my ContentView, from which I am presenting SettingsView:

enum ActiveSheet: Identifiable {
    case photoPicker, settings
    
    var id: Int {
        self.hashValue
    }
}

struct ContentView: View {
 
    @State var activeSheet: ActiveSheet?
    var body: some View {
        
        NavigationView {
            VStack {
                Text("Hello world")
                Button("Select Photo") {
                    self.activeSheet = .photoPicker
                }
            }
            .navigationBarTitle(Text("Title"), displayMode: .inline)
            .navigationBarItems(trailing: Button(action: {
                self.activeSheet = .settings
            }, label: {
                Image(systemName: "gear")
                    .imageScale(.large)
            }))
        }
        .sheet(item: $activeSheet) { item in
            if item == .photoPicker {
                ImagePicker(selectedImage: $image, sourceType: .photoLibrary)
            } else {
                SettingsView()
            }
        }
    }
}

Edit: I created a brand new project, this is the only code:

import SwiftUI

struct ContentView: View {
    @State private var currentSelection = 0
    var body: some View {
        NavigationView {
            Form {
                Section {
                    Picker("Test Picker", selection: $currentSelection) {
                        ForEach(0 ..< 100) { i in
                            Text(String(i)).tag(i)
                        }
                    }
                }

            }.navigationBarTitle(Text("Test"))
        }
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}

The issue still persists.

This may happen if you put `NavigationView` inside another `NavigationView`. Make sure your `SettingsView` is not inside a `NavigationView`. — pawello2222, Aug 08 '20 at 11:37
@pawello2222 I’m presenting it on using .sheet from my ContentView — Aryan C, Aug 08 '20 at 11:43
@pawello2222 I do have a ```NavigationView``` on my ContentView, however, the sheet modifier is outside it. — Aryan C, Aug 08 '20 at 11:52
@pawello2222 Hey, I've edited my post to show the ContentView — Aryan C, Aug 08 '20 at 12:02
What do you expect? By your code the picker settings is not stored anywhere. — Asperi, Aug 08 '20 at 12:50
@Asperi What do you mean by picker settings? I have a state variable bound to the picker. — Aryan C, Aug 08 '20 at 12:54
Screenshot shows that picker is in Form, but provided code does not have any Form. Did you try it? It shows wheel picker in sheet and that's it. — Asperi, Aug 08 '20 at 13:01
@Asperi ohh I see, sorry about that, the section is in a form, I’ll edit the post. — Aryan C, Aug 08 '20 at 13:04
@Asperi I just created a new project with a picker inside a section inside a form inside a navigation view, and the same issue persists — Aryan C, Aug 08 '20 at 13:05

user3124975 · Answer 1 · 2020-12-14T10:59:19.430

(For the record I am on Big Sur, Xcode 12.2 and this issue is still there.)

After few tests it appears that this behaviour is due to multiple lists inside the same View. You can see that the first "List" (i.e. UITableView) gets its selected row deselected when the navigation stack is popped back to the view, but this doesn't work for the lists after the first one. So clearly this is a bug (in SwiftUI?!).

The only way (and somehow a crappy way) I have found to circumvent this bug is to have the Introspect Library get the tableView of interest (in this case the one displaying the Form) and do some housekeeping like this:


import Introspect

...

public class Weak<T: AnyObject> {
   public weak var value: T?
   public init(_ value: T? = nil) {
     self.value = value
   }
}

private var listTableView = Weak<UITableView>()

var body: Some View {
   NavigationView {
      VStack {
        
        List {
          ...
        }
        
        Form {
          
          Picker(...) {
            ...
          }
        }
        .introspectTableView { listTableView.value = $0 }
        .onAppear() {
          
          if let tableView = listTableView.value, let indexPath = tableView.indexPathForSelectedRow {
             tableView.deselectRow(at: indexPath, animated: true)
          }

        }
}

It works... but with no animation though (anyone?).

This answer actually helped (SwitUI 2.0) and deserves being check-marked. Thx! — Vivienne Fosh, Feb 18 '21 at 11:29

Picker Row not getting deselected in Form (SwiftUI, Xcode 12 beta 4)

1 Answers1