在 Swift 中实现 Objective c 协议 [英] Implement Objective c protocol in Swift

问题描述

我在一个客观的 c 类中有这个协议:

I have this protocol in a objective c class:

@protocol YTManagerDelegate <NSObject>
@required
- (void)uploadProgressPercentage:(int)percentage;
@end
...

和一个连接到它的 swift 类:

and a swift class connected to it:

class YTShare: UIViewController, YTManagerDelegate{

    func uploadProgressPercentage(percentage:Int?){
        println(percentage)
    }
    ...

我收到错误:类型 YTShare 不符合 YTShareDelegate 协议，我可能错误地编写了 swift 函数，因此 obj 类找不到它.我怎样才能正确地写出来?

I receive the error: type YTShare does not conform to protocol YTShareDelegate, I have probably write incorrectly the swift function so the obj class don't find it. How I can write it correctly?

推荐答案

委托方法有两个错误

func uploadProgressPercentage(percentage:Int?){
    println(percentage)
}

参数不能是可选的，C类型int映射到Swift作为 CInt(Int32 的别名):

The parameter must not be an optional, and the C type int is mapped to Swift as CInt (an alias for Int32):

func uploadProgressPercentage(percentage:CInt){
    println(percentage)
}

或者，您可以在 Objective-C 协议中使用 NSInteger，即在 Swift 中映射到 Int.这将是一个 32 位或 64 位整数，具体取决于在架构上，而 int/CInt 总是 32 位.

Alternatively, you could use NSInteger in the Objective-C protocol, which is mapped to Int in Swift. This would be a 32-bit or 64-bit integer, depending on the architecture, whereas int/CInt is always 32-bit.

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