How to get all events from an EKCalendar in iOS - ios

Question

I've created a calendar with some events, now I want to get all events from that calendar, without knowing what their start or end date is.
Code I tried, getting all events from all calendars, so I could divide them by calendar ID later or so.. :
NSPredicate *fetchCalendarEvents = [eventStore predicateForEventsWithStartDate:[NSDate distantPast] endDate:[NSDate distantFuture] calendars:eventStore.calendars];
NSArray *allEvents = [eventStore eventsMatchingPredicate:fetchCalendarEvents];
This makes allEvents return nil while the database clearly shows events in the calendar.
Anyone could help me?

Answer 1

I have it working now.
This is the code I'm using:
NSDate* endDate = [NSDate dateWithTimeIntervalSinceNow:[[NSDate distantFuture] timeIntervalSinceReferenceDate]];
NSArray *calendarArray = [NSArray arrayWithObject:cal];
NSPredicate *fetchCalendarEvents = [eventStore predicateForEventsWithStartDate:[NSDate date] endDate:endDate calendars:calendarArray];
NSArray *eventList = [eventStore eventsMatchingPredicate:fetchCalendarEvents];
for(int i=0; i < eventList.count; i++){
NSLog(#"Event Title:%#", [[eventList objectAtIndex:i] title]);
}
Gives me all events from the calendar I'm using for my app from the date it is right when you call the method.
I think giving [NSDate distantPast] won't work because it's in the past or something.. setting your startDate as [NSDate date] will work.
Hope this helps people who have the same problem..

Answer 2

If you would like to lookup a year span greater than 4 years, the returned events would be trimmed by the system to those from the first 4 years. (see Apple's documentation). What could be a possible solution is to run the predicate matching in batches.
Here's a C# extension for Xamarin.iOS
public static class EKEventStoreExtensions
{
private const int MaxPredicateYearSpan = 4;
public static EKEvent[] GetAllEvents(this EKEventStore eventStore, DateTimeOffset startAt, DateTimeOffset endAt, params EKCalendar[] calendars)
{
var isBatched = endAt.Year - startAt.Year >= MaxPredicateYearSpan;
var result = new List<EKEvent>();
var batchStartAt = startAt;
var batchEndAt = endAt;
while (batchStartAt < endAt)
{
if (isBatched)
{
batchEndAt = batchStartAt.AddYears(1);
if (batchEndAt > endAt)
{
batchEndAt = endAt;
}
}
var events = GetEventsMatching(eventStore, batchStartAt, batchEndAt, calendars);
result.AddRange(events);
batchStartAt = batchEndAt;
}
return result.ToArray();
}
private static EKEvent[] GetEventsMatching(EKEventStore eventStore, DateTimeOffset startAt, DateTimeOffset endAt, EKCalendar[] calendars)
{
var startDate = (NSDate)startAt.LocalDateTime;
var endDate = (NSDate)endAt.LocalDateTime;
var fetchCalendarEvents = eventStore.PredicateForEvents(startDate, endDate, calendars);
return eventStore.EventsMatching(fetchCalendarEvents);
}
}