swift - 如何在 Swift 中为协议(protocol)指定一致的类

Question

我想知道是否可以创建一个协议(protocol)，其中它的方法引用符合类的类型

UHSyncObjectProtocol 协议(protocol)

protocol UHSyncObjectProtocol: class {
     func sync(completionBlock: ((UHSyncObjectProtocol) -> Void)?)
     // ideally, I want to refer to the conforming class instead of UHSyncObjectProtocol
} 

用户配置文件类

class UHUserProfile: UHSyncObjectProtocol {
     func sync(completionBlock: ((UHUserProfile) -> Void)?) {
        // do something
        completionBlock?(self)
     }
}

用户账户类

class UHUserAccount: UHSyncObjectProtocol {
     func sync(completionBlock: ((UHUserAccount) -> Void)?) {
        // do something
        completionBlock?(self)
     }
}

我不确定这是否可能。

Answer 1

你可以使用泛型来实现这一点

这里是例子

protocol UHSyncObjectProtocol: class {
    associatedtype T

    func sync(completionBlock: ((T) -> Void)?)
    // ideally, I want to refer to the conforming class instead of UHSyncObjectProtocol
}

class UHUserProfile: UHSyncObjectProtocol {
    func sync(completionBlock: ((UHUserProfile) -> Void)?) {
        // do something
        completionBlock?(self)
    }
}

class UHUserAccount: UHSyncObjectProtocol {
    func sync(completionBlock: ((UHUserAccount) -> Void)?) {
        // do something
        completionBlock?(self)
    }
}