I am trying to show a error message in a different view as in the below code

import Foundation

class apiCall: ObservableObject {
    func getUsers(completion:@escaping ([ResultItem]) -> ()) {
        
        let urlHeader=apiParams()
        URLSession.shared.dataTask(with: urlHeader) { (data, response , error) in
            let httpResponse = response as? HTTPURLResponse
            guard let data = data else { return }
           // print(String(data: data, encoding: .utf8) ?? "Invalid JSON")
            
                   do {
                       let result = try JSONDecoder().decode(Result.self,from: data)
                        completion(result.customerList)
                   } catch {
                   
                   completion([])
                   errorview()
                    print("error:", error.localizedDescription)
                   }
               }.resume()
        

        }
}

errorView() is a view file which i want to display when the code enters inside catch block, but currently I am getting blank screen and the details inside errorView is not getting displayed

//errorview page

import SwiftUI

struct errorview: View {
    var body: some View {
        Text(/*@START_MENU_TOKEN@*/"Hello, World!"/*@END_MENU_TOKEN@*/)
    }
}

struct errorview_Previews: PreviewProvider {
    static var previews: some View {
        errorview()
    }
}

I will modify the error message in this page once I am able to see this content from catch block

CodePudding user response：

try this approach as shown in this very basic example code, to "go" to the Errorview when your ApiCall, produces an error:

Adjust according to your needs:

struct ResultItem: Identifiable {
    let id = UUID()
    var name: String
    // ...
}

struct Errorview: View {
    @State var theError: APICallError?
    var body: some View {
        Text("Errorview: \(theError.debugDescription)")
    }
}

enum APICallError: Error {
    case decodingError
    case outOfLuck
    // ...
}

class ApiCall: ObservableObject {
    
    func getUsers(completion:@escaping ([ResultItem], APICallError?) -> ()) {
        let urlHeader = apiParams()  // <-- a URL or URLRequest here
        URLSession.shared.dataTask(with: urlHeader) { (data, response , error) in
            guard let data = data else {
                 completion([], APICallError.outOfLuck)
                 return
            }
            do {
                let result = try JSONDecoder().decode(Result.self,from: data)
                completion(result.customerList, nil)
            } catch {
                completion([], APICallError.decodingError)
            }.resume()
        }
    }
    
}

struct ContentView: View {
    @State var theError: APICallError?
    @State var actions: [Int] = []
    
    var body: some View {
        NavigationStack(path: $actions) {
            Text("ContentView")
                .navigationDestination(for: Int.self) { val in
                    Errorview(theError: theError)
                }
        }
        .onAppear {
            ApiCall().getUsers() { results, error in
                if error != nil {
                    theError = error
                    actions = [1]
                } else {
                    print("-----> results: \(results)")
                    // ....
                }
            }
        }
    }
}