How to add an event in the device calendar using swift?

Question

I would be interested in knowing how to add a calendar event in the device, but using swift. I know there are some examples made in Objective-C, but at the moment nothing in

Answer 1

This was really slow on iOS 11.2 Xcode 9.2, so I modified Luca Davanzo's answer to use queues (works a lot faster):

func addEventToCalendar(title: String, description: String?, startDate: Date, endDate: Date, completion: ((_ success: Bool, _ error: NSError?) -> Void)? = nil) {
        DispatchQueue.global(qos: .background).async { () -> Void in
            let eventStore = EKEventStore()

            eventStore.requestAccess(to: .event, completion: { (granted, error) in
                if (granted) && (error == nil) {
                    let event = EKEvent(eventStore: eventStore)
                    event.title = title
                    event.startDate = startDate
                    event.endDate = endDate
                    event.notes = description
                    event.calendar = eventStore.defaultCalendarForNewEvents
                    do {
                        try eventStore.save(event, span: .thisEvent)
                    } catch let e as NSError {
                        completion?(false, e)
                        return
                    }
                    completion?(true, nil)
                } else {
                    completion?(false, error as NSError?)
                }
            })
        }
    }