Question

我试图使用Swinject注入依赖，我不知道我做错了什么。

我有协议，处理registring用户。

protocol AuthServiceProtocol {
func registerUser(email: String, password: String, completion: @escaping CompletionHandler) }

和符合此协议的类构成了所有逻辑：

class AuthService: AuthServiceProtocol {
func registerUser(email: String, password: String, completion: @escaping CompletionHandler) {

        let lowerCaseMail = email.lowercased()
        let body: [String: Any] = [
            "email": lowerCaseMail,
            "password" : password
        ]

        Alamofire.request(URL_REGISTER, method: .post, parameters: body, encoding: JSONEncoding.default, headers: HEADER).responseString { (response) in
            if response.result.error == nil {
                completion(true)
            } else {
                completion(false)
                debugPrint(response.result.error as Any)
            }
        }
    }
}

所以，在AppDelegate中我们注册容器，它看起来像：

let container = Container() { container in
    container.register(AuthServiceProtocol.self) { _ in AuthService() }.inObjectScope(.container)
    container.register(CreateAccountVC.self) { r in
        let controller = CreateAccountVC()
        controller.authService = r.resolve(AuthServiceProtocol.self)
        return controller
    }
}

但在CreateAccountVC中，authService为空。任何想法我怎么能这样做？ CreateAccountVC是ViewController的子类，我尝试按属性和构造函数进行操作，但它始终没有。

Answer 1

检查您的代码：

var container : Container {
        let container = Container()
        container.register(AuthServiceProtocol.self) { _ in AuthService() }.inObjectScope(.container)
        container.register(CreateAccountVC.self) { r in
            let controller = CreateAccountVC()
            controller.authService = r.resolve(AuthServiceProtocol.self)
            print(r.resolve(AuthServiceProtocol.self))
            return controller
        }

        return container
    }

您已经计算了属性，每次调用它时，它都会创建一个新的Container对象。

重构你的代码以拥有一个容器，我相信你会很高兴。

修改

这是一个有效的代码段。下面是一个用于抽象具体DI服务的小包装类（如果Swinject被一天替换为其他东西）：

import Swinject public class ConfigurationProvider { // Currently using Swinject private let backingService = Container() // Singleton public static let shared = ConfigurationProvider() // Hidden initializer private init() {} // MARK: - Bind / Resolve public func bind<T>(interface: T.Type, to assembly: T) { backingService.register(interface) { _ in assembly } } public func resolve<T>(interface: T.Type) -> T! { return backingService.resolve(interface) } } // Extension methods to ignore 'shared.' call, like: // ConfigurationProvider.bind(interface: IAssembly, to: Assembly()) // ConfigurationProvider.resolve(interface: IAssembly) public extension ConfigurationProvider { static func bind<T>(interface: T.Type, to assembly: T) { ConfigurationProvider.shared.bind(interface: interface, to: assembly) } static func resolve<T>(interface: T.Type) -> T! { return ConfigurationProvider.shared.resolve(interface: interface) } }

用法：

class RSAuthLoginModuleAssembly: IAuthLoginModuleAssembly { } // Register: ConfigurationProvider.bind(interface: IAuthLoginModuleAssembly.self, to: ConcreteAuthLoginModuleAssembly()) // Resolve: guard let assembly = ConfigurationProvider.resolve(interface: IAuthLoginModuleAssembly.self) else { throw NSError(domain: "Assembly cannot be nil", code: 999, userInfo: nil) }

如何使用swinject正确地注入依赖项

1 个答案: