NotificationManager.swift

import UIKit

class NotificationManager {
    private var tokens = [String: AnyObject]()
    
    deinit {
        tokens.values.forEach { NC.removeObserver($0) }
    }
    
    func addObserver(forName name: NSNotification.Name, object obj: Any?, queue: OperationQueue?, using block: @escaping (Notification) -> Void) {
        tokens[name.rawValue] = NC.addObserver(forName: name, object: obj, queue: queue, using: block)
    }
}