Check out example codes for "swift notifications mac". It will help you in understanding the concepts better.

Code Example 1

func showNotification() -> Void {
    var notification = NSUserNotification()
    notification.title = "Test from Swift"
    notification.informativeText = "The body of this Swift notification"
    notification.soundName = NSUserNotificationDefaultSoundName
    NSUserNotificationCenter.default.deliver(notification)
}

self.showNotification()

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