Programmatically add custom event in the iPhone Calendar

Yes there still is no API for this (2.1). But it seemed like at WWDC a lot of people were already interested in the functionality (including myself) and the recommendation was to go to the below site and create a feature request for this. If there is enough of an interest, they might end up moving the ICal.framework to the public SDK.

https://developer.apple.com/bugreporter/

Update for swift 4 for Dashrath answer

import UIKit
import EventKit

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()

        let eventStore = EKEventStore()

        eventStore.requestAccess( to: EKEntityType.event, completion:{(granted, error) in

            if (granted) && (error == nil) {


                let event = EKEvent(eventStore: eventStore)

                event.title = "My Event"
                event.startDate = Date(timeIntervalSinceNow: TimeInterval())
                event.endDate = Date(timeIntervalSinceNow: TimeInterval())
                event.notes = "Yeah!!!"
                event.calendar = eventStore.defaultCalendarForNewEvents

                var event_id = ""
                do{
                    try eventStore.save(event, span: .thisEvent)
                    event_id = event.eventIdentifier
                }
                catch let error as NSError {
                    print("json error: \(error.localizedDescription)")
                }

                if(event_id != ""){
                    print("event added !")
                }
            }
        })
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }


}

also don't forget to add permission for calendar usage

Working code in Swift-4.2

import UIKit
import EventKit
import EventKitUI

class yourViewController: UIViewController{

    let eventStore = EKEventStore()

    func addEventToCalendar() {

    eventStore.requestAccess( to: EKEntityType.event, completion:{(granted, error) in
        DispatchQueue.main.async {
            if (granted) && (error == nil) {
                let event = EKEvent(eventStore: self.eventStore)
                event.title = self.headerDescription
                event.startDate = self.parse(self.requestDetails.value(forKey: "session_time") as? String ?? "")
                event.endDate = self.parse(self.requestDetails.value(forKey: "session_end_time") as? String ?? "")
                let eventController = EKEventEditViewController()
                eventController.event = event
                eventController.eventStore = self.eventStore
                eventController.editViewDelegate = self
                self.present(eventController, animated: true, completion: nil)

            }
        }


       })
    }

}

Now we will get the event screen and here you can also modify your settings:

Now add delegate method to handle Cancel and add the event button action of event screen:

    extension viewController: EKEventEditViewDelegate {

    func eventEditViewController(_ controller: EKEventEditViewController, didCompleteWith action: EKEventEditViewAction) {
        controller.dismiss(animated: true, completion: nil)

    }
}

Note: Don't forget to add NSCalendarsUsageDescription key into info plist.

The Google idea is a nice one, but has problems.

I can successfully open a Google calendar event screen - but only on the main desktop version, and it doesn't display properly on iPhone Safari. The Google mobile calendar, which does display properly on Safari, doesn't seem to work with the API to add events.

For the moment, I can't see a good way out of this one.