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Need help, simulator not working...

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Hi all. I have an error as Xcode isn’t letting me parse my JSON file data into an array. It says in the diagnostic report that “Fatal error: Fatal error: Couldn't parse Rest.json as Array<Restaurants>: The data couldn’t be read because it isn’t in the correct format.: So if anyone could help, I would appreciate it! I am trying to follow this tutorial, and the simulator is not working in the xcode file: RestaurantRows.swift

  • Harri

Tutorial: Github:


Did you not ask the same question Xcode 12.2, App and simulator crashing during parsing JSON file into array

Your JSON files is still incorrect you are missing { before the first line and } at after the last line, however I would take out the "restaurants": all together

then make a new Swift file with this in (I called Resaurant)

import Foundation

struct Restaurant: Decodable, Identifiable {
    let id: Int
    let name: String
    let imageName: String
    let description: String
    let category: String

make another new Swift file with in (called Bundle-Decodable)

import Foundation

extension Bundle {
    func decode<T: Decodable>(_ type: T.Type, from file: String, dateDecodingStrategy: JSONDecoder.DateDecodingStrategy = .deferredToDate, keyDecodingStrategy: JSONDecoder.KeyDecodingStrategy = .useDefaultKeys) -> T {
        guard let url = self.url(forResource: file, withExtension: nil) else {
            fatalError("Failed to locate \(file) in bundle.")

        guard let data = try? Data(contentsOf: url) else {
            fatalError("Failed to load \(file) from bundle.")

        let decoder = JSONDecoder()
        decoder.dateDecodingStrategy = dateDecodingStrategy
        decoder.keyDecodingStrategy = keyDecodingStrategy

        do {
            return try decoder.decode(T.self, from: data)
        } catch DecodingError.keyNotFound(let key, let context) {
            fatalError("Failed to decode \(file) from bundle due to missing key '\(key.stringValue)' not found – \(context.debugDescription)")
        } catch DecodingError.typeMismatch(_, let context) {
            fatalError("Failed to decode \(file) from bundle due to type mismatch – \(context.debugDescription)")
        } catch DecodingError.valueNotFound(let type, let context) {
            fatalError("Failed to decode \(file) from bundle due to missing \(type) value – \(context.debugDescription)")
        } catch DecodingError.dataCorrupted(_) {
            fatalError("Failed to decode \(file) from bundle because it appears to be invalid JSON")
        } catch {
            fatalError("Failed to decode \(file) from bundle: \(error.localizedDescription)")

PS read Paul's on how this is made How to decode JSON from your app bundle the easy way

then make a new SwiftUI View (called RestaurantRowView) with this in

import SwiftUI

struct RestaurantRowView: View {
    let restaurant: Restaurant

    var body: some View {
        HStack {
                .frame(width: 50, height: 50)
                .shadow(radius: 10)

            VStack(alignment: .leading) {


struct RestaurantRowView_Previews: PreviewProvider {
    static let restaurants = Bundle.main.decode([Restaurant].self, from: "Rest.json")

    static var previews: some View {
        RestaurantRowView(restaurant: restaurants[0])

ps please note the position of static let restaurants not in the static var previews

then in your RestaurantsView or ContentView put this in

import SwiftUI

struct RestaurantsView: View { // if using ContentView then use that here instead of RestaurantView
    let restaurants = Bundle.main.decode([Restaurant].self, from: "Rest.json")

    var body: some View {
        List(restaurants) { restaurant in
           RestaurantRowView(restaurant: restaurant)

struct RestaurantsView_Previews: PreviewProvider {
    static var previews: some View {

If you want to look at the Project that tested this with here on GitHub

Happy coding


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