MyTestClass.h

//
//  MyTestClass.h
//
//  Created by Don Mag on 2/28/19.
//

#import <Foundation/Foundation.h>

#ifndef MyTestClass_h
#define MyTestClass_h

@interface MyTestClass : NSObject

- (void) someMethod:(NSInteger) secondsDelay;

@end

#endif /* MyTestClass_h */

MyTestClass.m

//
//  MyTestClass.m
//
//  Created by Don Mag on 2/28/19.
//

#import "MyTestClass.h"

@implementation MyTestClass

- (void) someMethod:(NSInteger) secondsDelay {
	
	NSLog(@"SomeMethod executing with secondsDelay of: %ld", (long)secondsDelay);
	
	NSDictionary *userInfo = [NSDictionary dictionaryWithObjectsAndKeys:
							  @"Value 1", @"Key1",
							  @"Value 2", @"Key2",
							  nil];
	
	dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(secondsDelay * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{

		NSLog(@"Posting Notification...");
		
		[[NSNotificationCenter defaultCenter] postNotificationName:@"openBoard" object:nil userInfo:userInfo];
		
	});

}

@end

ProjName-Bridging-Header.h

//
//  Use this file to import your target's public headers that you would like to expose to Swift.
//

#import "MyTestClass.h"

ViewController.swift

//
//  ViewController.swift
//
//  Created by Don Mag on 2/28/19.
//

import UIKit

class ViewController: UIViewController {

	override func viewDidLoad() {
		super.viewDidLoad()

		// register to receive the notification
		NotificationCenter.default.addObserver(self, selector: #selector(self.openBoard(notification:)), name: Notification.Name("openBoard"), object: nil)

		let sDelay = 2
		
		print("Calling someMethod:(NSInteger) secondsDelay - should get notification in \(sDelay) seconds...")

		let instanceOfCustomObject: MyTestClass = MyTestClass()
		instanceOfCustomObject.someMethod(sDelay)
		
	}

	@objc func openBoard(notification: Notification) {
		
		print("Got Notif!")
		
		if let data = notification.userInfo as? [String: String] {
			for (k, v) in data {
				print("\(k) : \(v)")
			}
		}

	}
	
}