WatchKit animation with completion block

WatchKitAnimCompletion.swift

extension WKInterfaceController {
    func animate(withDuration duration: TimeInterval, animations: @escaping () -> Swift.Void, completion: @escaping () -> Swift.Void) {
        self.animate(withDuration: duration, animations: animations)
        DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + duration, execute: completion)
    }
}