Fetching from JSON SwiftUI

Question

Created Jan ’21

Replies 9

Boosts 0

Views 3.3k

Participants 2

Hello
I'm trying to fetch some data from a JSON Api, but when I access the properties of my struct it tells me Value of Type "Name Of The Struct" has no member "name of the property"
Any idea on how to fix it
Code:

Code Block import SwiftUI
import Combine
struct ContentView: View {
    
    @ObservedObject var networkController = NetworkControllerItalia()
    var gridItemLayout = [GridItem(.flexible()), GridItem(.flexible())]
    
    var body: some View {
        NavigationView{
            ScrollView{
                ForEach(networkController.users, id: \.self){ user in
                    GroupBox(label: Text(user.round ?? ""), content: {
                        VStack{
                            Text(user.team1 ?? "")
                        }
                    }).padding()
            }
            .navigationTitle("Serie A")
        }
     }
   }
}
class NetworkControllerItalia: ObservableObject {
    private var can: AnyCancellable?
    
    let url = URL(string: "https://raw.githubusercontent.com/openfootball/football.json/master/2020-21/it.1.json")!
    //let url = URL(string: "google.com")!
    @Published var users = [UserItalia(matches: [])]
    
    init() {
        self.can = URLSession.shared.dataTaskPublisher(for: url)
            .map { $0.data }
            .decode(type: [UserItalia].self, decoder: JSONDecoder())
            //.replaceError(with: [])
            .eraseToAnyPublisher()
            .receive(on: DispatchQueue.main)
            .sink(receiveCompletion: {completion in
                print(completion)
            }, receiveValue: { users in
                self.users  = users
            })
    }
    
}
struct UserItalia: Decodable, Hashable {
    var matches: [Matches]?
}
struct Matches: Decodable, Hashable {
    var round: String?
    var date: String?
    var team1: String?
    var team2: String?
}

Thank You

Answered by Claude31 in 656540022

'ForEach' requires that 'UserItalia' conform to 'RandomAccessCollection'

Of course, UserItalia is not an array.
You need to understand better what your data structures are.

networkController.users is UserItalia type.

What you want to access are matches, isn't it ?

So, you should write something like this

Code Block                 ForEach(networkController.users.matches ?? [], id: \.self){ match in
                    GroupBox(label: Text(match.round ?? ""), content: {
                        VStack{
                            Text(match.team1 ?? "")
                        }
                    }).padding()

I tested and it works (iOS 14.2).

If that's OK, don't forget to close the thread on this answer, otherwise please detail the exact error you get.

Boost

Answer 1

Claude31 OP

Jan ’21

but when I access the properties of my struct it tells me Value of Type "Name Of The Struct" has no member "name of the property"

Do you mean "Matches has no member someName" ?

Could you show the JSON you get to check the coding keys ?
Why don't you define CodingKeys ?

0

Answer 2

Jad-T OP

Jan ’21

I never used CodingKeys (I don't know what it's used for), but if it solves the problem I could include it
The JSON file is in the URL at line 28

It says Value of type UserItalia has no member team1.

0

Answer 3

Claude31 OP

Jan ’21

OK, here is an extract from json
You could have made the effort to get it and post it yourself, isn't it ?

Code Block {
  "name": "Serie A 2020/21",
  "matches": [
    {
      "round": "1^ Giornata",
      "date": "2020-09-19",
      "team1": "ACF Fiorentina",
      "team2": "Torino FC",
      "score": {
        "ft": [
          1,
          0
        ]
      }
    },
    {
      "round": "1^ Giornata",
      "date": "2020-09-19",
      "team1": "Hellas Verona",
      "team2": "AS Roma",
      "score": {
        "ft": [
          3,
          0
        ]
      },
      "status": "AWARDED"
    },
    {
      "round": "1^ Giornata",
      "date": "2020-09-20",
      "team1": "Parma",
      "team2": "SSC Napoli",
      "score": {
        "ft": [
          0,
          2
        ]
      }
    },

The error is on lines 30 and 35 where you pass an array.

Just pass:

Code Block     @Published var users = UserItalia(matches: [])

and

Code Block             .decode(type: UserItalia.self, decoder: JSONDecoder())

You could also decode the complete JSON:

Code Block struct Score: Decodable, Hashable {
    var ft: [Int]?
}
struct Matches: Decodable, Hashable {
    var round: String?
    var date: String?
    var team1: String?
    var team2: String?
    var score: Score?
    var status: String?
}
struct UserItalia: Decodable, Hashable {
    var name: String?
    var matches: [Matches]?
}

0

Answer 4

Jad-T OP

Jan ’21

yes but now it gave me an error at line 13: Referencing initializer 'init(_:content:)' on 'ForEach' requires that 'UserItalia' conform to 'RandomAccessCollection'
I tried to change \.self with name but it didn't work

0

Answer 5

Claude31 OP

Jan ’21

Accepted Answer

'ForEach' requires that 'UserItalia' conform to 'RandomAccessCollection'

Of course, UserItalia is not an array.
You need to understand better what your data structures are.

networkController.users is UserItalia type.

What you want to access are matches, isn't it ?

So, you should write something like this

Code Block                 ForEach(networkController.users.matches ?? [], id: \.self){ match in
                    GroupBox(label: Text(match.round ?? ""), content: {
                        VStack{
                            Text(match.team1 ?? "")
                        }
                    }).padding()

I tested and it works (iOS 14.2).

If that's OK, don't forget to close the thread on this answer, otherwise please detail the exact error you get.

0

Answer 6

Jad-T OP

Jan ’21

You need to understand better what your data structures are.

Maybe it's because I started programming/developing few weeks ago.
It worked, Thank you very much

0

Answer 7

Jad-T OP

Jan ’21

I have the last question, is it possible (in the same ForEach) to display score.ft ?

0

Answer 8

Claude31 OP

Jan ’21

If it works, thanks to mark this answer as correct.

From there you can also print the score:

Code Block 						ForEach(networkController.users.matches ?? [], id: \.self){ match in
								GroupBox(label: Text(match.round ?? ""), content: {
										VStack {
												HStack {
														Text(match.team1 ?? "")
														Text(" - ")
														Text(match.team2 ?? "")
												}
												HStack {		// THIS HStack is not needed, unless you want to add some other text in line.
														Text(match.score == nil ? "" : "\(match.score!.ft![0]) - \(match.score!.ft![1])")
												}
										}
								}).padding()

0

Answer 9

Jad-T OP

Jan ’21

Thank you for your time, every thing is working

0