由于“内部”保护级别，初始化程序不可访问

Question

我有一些协议

登录策略

public protocol LoginStrategy {
    func login(_ viewController: UIViewController)
    func getUserInfo(withCompletionHandler completionHandler: @escaping (_ userInfo: [String: Any]?) -> ())
    func createLoginButton(_ frame: CGRect, withCompletionHandler completionHandler: @escaping (_ loginButton: UIView) -> ())
    func getUserId() -> String
}

和两个班级：

登录提供者

public class LoginProvider {

    public let strategy: LoginStrategy

    public func login(_ viewController: UIViewController) {
        return self.strategy.login(viewController)
    }

    public func getUserInfo(withCompletionHandler completionHandler: @escaping (_ userInfo: [String: Any]?) -> ()) {
        return self.strategy.getUserInfo(withCompletionHandler: completionHandler)
    }

    public func createLoginButton(_ frame: CGRect, withCompletionHandler completionHandler: @escaping (_ loginButton: UIView) -> ()) {
        return self.strategy.createLoginButton(frame, withCompletionHandler: completionHandler)
    }

    public func getUserId() -> String {
        return self.strategy.getUserId()
    }

    public init(strategy: LoginStrategy) {
        self.strategy = strategy
    }

}

Facebook登录策略

import Foundation
import FacebookCore
import FacebookLogin

public class FacebookLoginStrategy: LoginStrategy {

    public var grantedPermissions: Set<Permission>? = nil

    public var declinedPermissions: Set<Permission>? = nil

    public var userId: String = ""

    public func login(_ viewController: UIViewController) {
        let loginManager = LoginManager()
        let permissions: [ReadPermission] = [.publicProfile, .userFriends, .email]
        loginManager.logIn(permissions, viewController: viewController) { loginResult in
            switch loginResult {
            case .failed(let error):
                print(error)
            case .cancelled:
                print("User cancelled login.")
            case .success(let grantedPermissions, let declinedPermissions, let accessToken):
                self.userId = accessToken.userId ?? ""
                self.grantedPermissions = grantedPermissions
                self.declinedPermissions = declinedPermissions
                print("Logged in!")
            }
        }
    }

    public func getUserId() -> String {
        return userId
    }

    public func getUserInfo(withCompletionHandler completionHandler: @escaping (_ userInfo: [String: Any]?) -> ()) {
        let request = GraphRequest(graphPath: "me", parameters: ["fields":"email, name"], accessToken: AccessToken.current, httpMethod: .GET, apiVersion: FacebookCore.GraphAPIVersion.defaultVersion)
        request.start { (response, result) in
            switch result {
            case .success(let value):
                print(value.dictionaryValue)
                completionHandler(value.dictionaryValue)
            case .failed(let error):
                print(error)
            }
        }
    }

    public func createLoginButton(_ frame: CGRect, withCompletionHandler completionHandler: @escaping (_ loginButton: UIView) -> ()) {
        let permissions: [ReadPermission] = [.publicProfile, .userFriends, .email]
        let loginButton = LoginButton(readPermissions: permissions)
        loginButton.frame = frame
        completionHandler(loginButton)
    }
}

在我的ViewController中：

当我使用：

let facebookLoginProvider = LoginProvider(strategy: FacebookLoginStrategy())

它说：

由于“内部”保护级别，“FacebookLoginStrategy”无法访问

Answer 1

只需添加到您的 FacebookLoginStrategy：

public init() {}

只要您不显式实现 init()，它就会默认标记为内部。 您需要覆盖该权限级别才能从框架外部进行实例化。

Answer 2

如果您在 XCTestCase 中的代码中运行此操作，请确保已将@testable import My-Awesome-App添加到测试文件的顶部。

Answer 3

将 init 方法添加为公共访问

public init() {}

Answer 4

如果有人在实现 Swift 包以构建可重用的 SwiftUI 视图时遇到这个问题，有几件事要记住。

1. 如果有从父组件设置的组件道具，不要忘记将它们添加到构造函数
2. 如果属性用@State包装，则将状态分配给底层对象，如下所示。

public struct Layout: View {
    @State var layout: NavType = .TOP
    var navItems: [NavItemObject]
    public init(layout: NavType, navItems: [NavItemObject]) {
        _layout = State(initialValue: layout);
        self.navItems = navItems;
    }
}