UIResponder Extension -- To get any type of responder if exists in hierarchy

Using Swift
,
1

extension UIResponder {

func chainedResponderOf<T: Any>(type responderClassType: T) -> UIResponder? {

    guard let classType = responderClassType as? AnyClass else { return nil }
    
    var responder: UIResponder? = self.next

    while responder != nil {
        
        if responder!.isKind(of: classType) {
            return responder!
        }
        responder = responder!.next
    }
    
    return nil
}

}

1 Like
2

Hi Fahid,

I expect this is a suggestion for an extension on UIKit for the Swift Interface? If so, unfortunately UIKit is out of scope for our modification. That said, it may be a good suggestion for Feedback Assistant that Apple could include for UIKit, and could also be useful for others using Swift anyway in their own codebase!

Rod

1 Like
3

As a matter of interest, this might be a cleaner implementation?

extension UIResponder {

    func chainedResponder<T: UIResponder>(of responderType: T.Type) -> T? {

        return sequence(first: self, next: { $0.next })
                       .dropFirst()    // Drop the first one as it will be self
                       .first(where: { $0 is T }) as? T
    }
}
2 Likes
4

Thanks @Rod_Brown

What is the way to suggest Apple to add this in UIKit?

5

Apple has recently switched to using native apps for bug reports and feature requests. You can find out more here: