Conform to NSMutableCopying in Swift?

Question

My question is simple: what is the best way to conform to the NSMutableCopying protocol on my own Swift class (possibly with some code explanation)?

 class CustomClass: NSObject, NSMutableCopying {
    var string1: String
    var string2: String

    required override init() {
        self.string1 = "string1"
        self.string2 = "string2"
    }

    // MARK: NSMutableCopying ??

}

Answer 1

In Objc, I use:

+ (instancetype)allocWithZone:(struct _NSZone *)zone OBJC_SWIFT_UNAVAILABLE("use object initializers instead");

but this method unavailable in Swift.

So I implement like this:

class CustomClass: NSObject, NSMutableCopying {
    var string1: String
    var string2: String

    required override init() {
        self.string1 = "string1"
        self.string2 = "string2"
    }

    func mutableCopyWithZone(zone: NSZone) -> AnyObject {
        let customObject = CustomClass()
        customObject.string1 = string1
        customObject.string2 = string2
        return customObject
    }
}

i'm not sure whether right or not, but i can't think of a better way.

Continuous attention..