In my ViewModel I'm fetching data from API and I want to populate my variable with the data, however when I declare the variable, it returns error.

ViewModel.swift

class PromoDetailViewModel: ObservableObject, ModelService {
    var apiSession: APIService
    
    @Published var dataArray = [BannerDetailResData]() // This is okay
    @Published var data = BannerDetailResData // This returns error

    // Error message is:
    // Expected member name or constructor call after type name
    // Add arguments after the type to construct a value of the type
    // Use .self to reference the type object

    init(apiSession: APIService = APISession()) {
        self.apiSession = apiSession
    }
    
    func getPromoDetail() {
        let cancellable = self.getBannerDetail(bannerID: bannerID)
            .sink(receiveCompletion: { result in
                switch result {
                case .failure(let error):
                    print("Handle error: \(error)")
                case .finished:
                    break
                }
                
            }) { (result) in
                if result.statusCode == 200 {
                    self.data = result.data
                }
                self.isLoading = false
            }
        cancellables.insert(cancellable)
    }
}

BannerDetailResData.swift

struct BannerDetailResData: Codable, Hashable {
    let bannerId: String
    let bannerImg: String
    let startDate: String
    let endDate: String
}

Why is it when I declare as BannerDetailResData, it works perfectly? What is the correct way of declaring this single struct object? Thank you in advance

CodePudding user response：

Make it optional

@Published var data:BannerDetailResData?