title: SwiftUI Picker in a Form doesn't show the selected row
body: <p>I am trying to have a Picker that shows which option is currently selected. </p>
  
  <p>Try out the following code which correctly selects the right option but the picker does not show which option is selected: </p>
  
  <pre><code>import SwiftUI
  
  struct ContentView: View {
  @State var selectedIndex: Int = 0
  
  let strings: [String] = {
      var strings: [String] = []
      for i in 0..&lt;10 {
          strings.append("\(i)")
      }
      return strings
  }()
  
  var body: some View {
      NavigationView {
          VStack {
              Form {
                  Picker(selection: $selectedIndex,
                         label: Text("Selected string: \(strings[selectedIndex])")) {
                      ForEach(0..&lt;strings.count) {
                          Text(self.strings[$0]).tag($0)
                      }
                  }
              }
          }
          .navigationBarTitle("Form Picker",
                              displayMode: NavigationBarItem.TitleDisplayMode.inline)
      }
  }
  
  }
  
  struct ContentView_Previews: PreviewProvider {
      static var previews: some View {
          ContentView()
      }
  }
  </code></pre>
  
  <p>Anyone know what could be wrong? It's observed using Xcode 11.1 and iOS 13.1 </p>