Extending a Swift class with Objective-C category

Question

Im in a situation where I need to use Objective-C category to extend a Swift class. I\'ve done something as follows:

In \"SomeClass.swift\":

class So         


        

Answer 1

From the Interoperability guide, we cannot directly access the subclassed / categorized / extensioned Objc-objects for the .swift [SomeClass] class.

But as a turn-around, we can do this:

For Variables , we can do this:

extension Class {
    private struct AssociatedKeys {
        static var DescriptiveName = "sh_DescriptiveName"
    }

    var descriptiveName: String? {
        get {
            return objc_getAssociatedObject(self, &AssociatedKeys.DescriptiveName) as? String
        }

        set {
            if let newValue = newValue {
                objc_setAssociatedObject(
                    self,
                    &AssociatedKeys.DescriptiveName,
                    newValue as NSString?,
                    .OBJC_ASSOCIATION_RETAIN_NONATOMIC
                )
            }
        }
    }
}

For Methods, we can use method_swizzling which is not recommended.