Swift. Event not saving to calendar - ios

Question

I'm trying to copy specific events from all calendars to the target calendar. Unfortunately my events are not saving in target calendar.
Simply my code in steps:
Check permissions (success)
Load calendars (success)
Load events (success)
Save events (failed)
I'm sure there are events to save from terminal which prints "Trying to save" couple of times.
And it looks like code pass through "try self.eventStore.save(event, span: .thisEvent)" and exits function there without calling "Saved" or entering catch clause.
There is a source code:
import UIKit
import EventKit
class ViewController: UIViewController{
#IBOutlet weak var status: UILabel!
var calendars: [EKCalendar]?
var targetCalendar: EKCalendar?
var targetCalendarEvents: [EKEvent]?
let eventStore = EKEventStore()
let targetCalendarName = "TargetCalendarName"
override func viewDidLoad() {
super.viewDidLoad()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
override func viewWillAppear(_ animated: Bool) {
DispatchQueue.main.async{
self.status.text = "Idle"
}
checkCalendarAuthorizationStatus()
}
func checkCalendarAuthorizationStatus() {
let status = EKEventStore.authorizationStatus(for: EKEntityType.event)
switch (status) {
case EKAuthorizationStatus.notDetermined:
// This happens on first-run
requestAccessToCalendar()
case EKAuthorizationStatus.authorized:
// Things are in line with being able to show the calendars in the table view
loadCalendars()
loadEvents()
case EKAuthorizationStatus.restricted, EKAuthorizationStatus.denied:
// We need to help them give us permission
print("Missing permissions [00]")
}
}
func requestAccessToCalendar() {
eventStore.requestAccess(to: EKEntityType.event, completion: {
(accessGranted: Bool, error: Error?) in
if accessGranted == true {
DispatchQueue.main.async(execute: {
self.loadCalendars()
self.loadEvents()
})
} else {
print("Missing permissions [01]")
}
})
}
func loadEvents(){
print("Loading..")
DispatchQueue.main.async{
self.status.text = "Loading"
}
let eventStore = EKEventStore()
var initialized = false
//Two months
let dateTo = NSDate(timeIntervalSinceNow: +30*24*3600 * 2)
for calendar in self.calendars! {
let predicate = eventStore.predicateForEvents(withStart: Date() as Date as Date, end: dateTo as Date, calendars: [calendar])
let events = eventStore.events(matching: predicate)
if calendar.title == targetCalendarName {
print("Initialized")
targetCalendar = calendar
targetCalendarEvents = events
initialized = true
}
}
if(!initialized){
print("Not Initialized")
} else {
for calendar in self.calendars! {
let predicate = eventStore.predicateForEvents(withStart: Date() as Date as Date, end: dateTo as Date, calendars: [calendar])
let events = eventStore.events(matching: predicate)
if calendar.title != targetCalendarName && calendar.title != "Contacts" {
//print("Loaded Calendar \(calendar.title)")
print("Loaded Calendar")
for event in events {
if(!(event.location?.isEmpty)!){
//print("Event \(event.location ?? "Missing Location") \(event.startDate) \(event.endDate)")
addEventToTarget(eventToAdd: event)
}
}
}
}
}
DispatchQueue.main.async {
self.status.text = "Done"
}
print("Done")
}
func loadCalendars() {
self.calendars = eventStore.calendars(for: EKEntityType.event)
}
func addEventToTarget(eventToAdd: EKEvent){
eventStore.requestAccess(to: .event) { (granted, error) in
for event in self.targetCalendarEvents! {
if(!(event.location?.isEmpty)!){
if(
eventToAdd.title == event.title &&
eventToAdd.startDate == event.startDate &&
eventToAdd.endDate == event.endDate
){
print("Possible duplicate - skipping")
return
}
}
}
if (granted) && (error == nil) {
let event:EKEvent = EKEvent(eventStore: self.eventStore)
event.title = eventToAdd.title
event.startDate = eventToAdd.startDate
event.endDate = eventToAdd.endDate
event.notes = ""
event.location = eventToAdd.location
event.calendar = self.targetCalendar
//print("Trying to save \(event.title) \(String(describing: event.location))")
print("Trying to save")
do {
try self.eventStore.save(event, span: .thisEvent)
print("Saved \(event.title) \(String(describing: event.location)) in \(event.calendar.title)")
} catch {
print("failed to save event with error : \(error as NSError)")
}
}
else{
print("failed to save event with error : \(String(describing: error)) or access not granted")
}
}
}
}
TargetCalendarName is correct calendar name
Sometimes there are events which saves successfully but only couple of them (2-5) for hundreds which should save. I don't have a clue why.
So 5 for 200 is not enough for me.

Answer 1

Thanks to #matt for proposing a solution.
Now I'm saving events ONCE (previously I was requesting access for every event which is very bad), so I request access to eventStore once and can save events succesfully.
func saveEvents(){
eventStore.requestAccess(to: .event) { (granted, error) in
if (granted) && (error == nil) {
for event in self.eventsToCopy {
print("Trying to save")
do {
try self.eventStore.save(event, span: .thisEvent)
print("Saved \(event.title) \(String(describing: event.location)) in \(event.calendar.title)")
} catch {
print("failed to save event with error : \(error as NSError)")
}
}
}
else{
print("failed to save event with error : \(String(describing: error)) or access not granted")
}
}
}