"Expected to decode Dictionary<String, Any> but found an array instead.", underlyingError: nil; GitHub repo showing app; SwiftUI

Question

我需要创建一个能够 return GitHub 用户拥有的所有存储库的应用程序。

我创建了一个包含 3 个文件的应用程序：内容视图

import SwiftUI

struct ContentView: View {
    
    @StateObject var netManager = NetworkingManager()
    
    
    var body: some View {
            List {
                ForEach(netManager.owner) { item in
                    Text(item.reposUrl)
                }
        }
    }
}

API 按键

import Foundation

struct Root : Decodable, Identifiable {
    let id: Int
    let items : [Repository]
}

struct Repository: Decodable, Identifiable {
    let id: Int
    let name, fullName: String
    let owner : Owner
}

struct Owner : Decodable, Identifiable {
    let id: Int
    let reposUrl : String
}

DECODERS（因为我知道我以后需要另一个，除非我能足够抽象这个）

class NetworkingManager: ObservableObject{
    @Published var owner = [Owner]()
    
    init() {
            loadData()
        }

        func loadData() {
            guard let url = URL(string: "https://api.github.com/users/jacobtoye/repos") else { return }
            URLSession.shared.dataTask(with: url) {(data, _, _) in
                guard let data = data else { return }
                do {
                    let response = try JSONDecoder().decode(Owner.self, from: data)
                } catch {
                    print("error: \(error)")
                }
                
            }.resume()
        }
        
    }

代码运行良好，但我没有得到任何结果（第一个屏幕是空白的），我想在那里查看所选用户存储库的列表。你能帮我解码字典吗？

我也想知道问题不在于我也没有使用 convertFromSnakeCase 密钥解码策略，但是当 JSONDecoder 被包装在常量中时，我不知道如何把它放在那里。

Answer 1

对于极简主义的工作示例代码，试试这个：

struct Repository: Decodable, Identifiable {
    let id: Int
    let name, fullName: String
    let owner: Owner
    
    enum CodingKeys: String, CodingKey {
        case id, name, owner
        case fullName = "full_name"  // <-- here
    }
}

struct Owner : Decodable, Identifiable {
    let id: Int
    let reposUrl : String

    enum CodingKeys: String, CodingKey, CaseIterable {
        case id
        case reposUrl = "repos_url"  // <-- here
    }
}

class NetworkingManager: ObservableObject{
    @Published var owner = [Owner]()
    
    init() {
        loadData()
    }
    
    func loadData() {
        guard let url = URL(string: "https://api.github.com/users/jacobtoye/repos") else { return }
        URLSession.shared.dataTask(with: url) {(data, _, _) in
            guard let data = data else { return }
            DispatchQueue.main.async { // <-- here
                do {
                    let repos = try JSONDecoder().decode([Repository].self, from: data)  // <-- here
                    repos.forEach{ self.owner.append([=10=].owner) }
                } catch {
                    print("error: \(error)")
                }
           }
        }.resume()
    }
}

struct ContentView: View {
    @StateObject var netManager = NetworkingManager()
    
    var body: some View {
        List {
            ForEach(netManager.owner) { item in
                Text(item.reposUrl)
            }
        }
    }
}

这应该给你一个 "https://api.github.com/users/jacobtoye/repos" 的列表，因为这是数据的组成部分。

EDIT-1：列出所有回购

class NetworkingManager: ObservableObject{
    @Published var repos = [Repository]() // <-- here repos
    
    init() {
        loadData()
    }
    
    func loadData() {
        guard let url = URL(string: "https://api.github.com/users/jacobtoye/repos") else { return }
        URLSession.shared.dataTask(with: url) {(data, _, _) in
            guard let data = data else { return }
            DispatchQueue.main.async { // <-- here
                do {
                    self.repos = try JSONDecoder().decode([Repository].self, from: data)  // <-- here
                } catch {
                    print("error: \(error)")
                }
            }
        }.resume()
    }
}

struct ContentView: View {
    @StateObject var netManager = NetworkingManager()
    
    var body: some View {
        List {
            ForEach(netManager.repos) { repo in
              VStack {
                Text(repo.fullName).foregroundColor(.blue)
                Text(repo.owner.reposUrl)
              }
            }
        }
    }
}

Answer 2

一个小修改，在我最近的项目之后，在上面建议的解决方案中，如果闭包中没有传递更多参数，则更好地使用[weak self]：

 guard let url = URL(string: "https://api.github.com/users/jacobtoye/repos") else { return }
    URLSession.shared.dataTask(with: url) { [weak self] (data, _, _) in
        guard let self = self, let data = data else { return }

而不是

guard let url = URL(string: "https://api.github.com/users/jacobtoye/repos") else { return }
        URLSession.shared.dataTask(with: url) {(data, _, _) in
            guard let data = data else { return }

由于这种方法，您可以防止内存泄漏，这可能会使您的应用在一天结束时变慢。

"Expected to decode Dictionary<String, Any> but found an array instead.", underlyingError: nil; GitHub repo showing app; SwiftUI

"Expected to decode Dictionary<String, Any> but found an array instead.", underlyingError: nil; GitHub repo showing app; SwiftUI

api

swiftui

urlsession