SwiftUI: How do I loop through an array of Int inside "For Each"

Question

I am getting the following error "Closure containing control flow statement cannot be used with function builder 'ViewBuilder'" Not able to find similar troubleshoot anywhere.

struct FavoriteView: View {
    @EnvironmentObject var userData: UserData
    @State var isfavorite = false
    var favoriteindex = [1,2,3]

    var body: some View {
       NavigationView {
          List {
             ForEach(userData.labvaluesUserdata) {section in
                for numbers in favoriteindex {
                   if section.id == (numbers) {
                      ItemRow(list: section)
                   }
                }
            }
         }
      }
   }
}

With this I am able to get the first index. Any simple way to loop through ?

List {
   ForEach(userData.labvaluesUserdata) { section in
      if section.id == self.favoriteindex.first {
         ItemRow(list: section)
      }
   }
}

Did you see this: jasonzurita.com/swiftui-if-statement - it has exactly that error and a potential workaround. — koen
– koen, Commented Nov 27, 2019 at 16:00
Might have something to do with 7 LEFT braces, and only 5 Right braces ? — donPablo
– donPablo, Commented Nov 27, 2019 at 16:04
Yeah had seen that. But that is for a Bool value. For me, I need to loop over each integer in the array "favoriteindex" @koen — Dar
– Dar, Commented Nov 27, 2019 at 16:05
@donPablo thanks for pointing out that. But that was due to error in pasting the code here as I had to reduce some navigation bar code. I have edited the code now. — Dar
– Dar, Commented Nov 27, 2019 at 16:11

Denis Vert · Accepted Answer · 2019-12-18 21:26:53Z

2

You can do it, and it's simple as that

enum SectionType: Identifiable {
    var id: Int {
        switch self {
        case .first:
            return 1
        case .second:
            return 2
        case .third:
            return 3
        }
    }

    case first
    case second
    case third
}

struct UserData {
    var labvaluesUserdata: [SectionType] = [.first, .second, .third, .first, .second]
}

struct ItemRow: View {
    var list: SectionType

    var body: some View {
        Text("\(list.id)")
    }
}

struct ContentView: View {
    @State var userData = UserData()
    @State var favoriteindex: [Int] = [2, 3]

    var body: some View {
        NavigationView {
            List {
                ForEach(userData.labvaluesUserdata) {section in
                    if self.favoriteindex.contains(where: { $0 == section.id }) {
                        ItemRow(list: section)
                    }
                }
            }
        }
    }
}

Updated: added brand new solution. Tried it and it works

edited Dec 18, 2019 at 21:26

answered Nov 27, 2019 at 22:57

Denis Vert

3666 silver badges14 bronze badges

Sign up to request clarification or add additional context in comments.

5 Comments

Dar Over a year ago

What is SectionType here ? I am getting this error "Use of undeclared type 'SectionType' "

Denis Vert Over a year ago

oh, man It's type of your section in labvaluesUserdata array. So just replace it with your values type of labvaluesUserdata array.

Dar Over a year ago

Nope!!! labvaluesUserdata is an array of Struct. I get this error ii I use "MTLStruct Type" ...Cannot invoke initializer for type 'ForEach<_, _, _>' with an argument list of type '([Labvalueslist], @escaping (MTLStructType) -> some View)'

Dar Over a year ago

I was able to go further but held up here stackoverflow.com/questions/59268923/…

Denis Vert Over a year ago

@Dar I've updated my answer. Check it. Also it solves stackoverflow.com/questions/59268923/… So you can close it if it's possible.

Collectives™ on Stack Overflow

SwiftUI: How do I loop through an array of Int inside "For Each"

1 Answer 1

5 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

5 Comments

Your Answer

Sign up or log in

Post as a guest

Related