Manage iPhone Calendar event from our application

The following is my code

NSLog(@"%@", thisEvent1.title); 

EKEvent *thisEvent  = [EKEvent eventWithEventStore:eventStore];

eventStore = [[EKEventStore alloc] init];

thisEvent = [EKEvent eventWithEventStore:eventStore];


NSDateFormatter *   dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:@"yyyy-MM-dd:HH:mm"];


NSDate * date = [[NSDate alloc] init];
date = [dateFormatter dateFromString:[itsStartDate objectAtIndex:indexPath.row]];
[date retain];

thisEvent.startDate = [dateFormatter dateFromString:[itsStartDate objectAtIndex:indexPath.row]];
thisEvent.endDate = [dateFormatter dateFromString:[itsEndDate objectAtIndex:indexPath.row]];
thisEvent.notes = [itsNotes objectAtIndex:indexPath.row];
thisEvent.title = [itsTitle objectAtIndex:indexPath.row];
thisEvent.location = [itsLocation objectAtIndex:indexPath.row];
// thisEvent.allDay = TRUE;
NSMutableArray *myAlarmsArray = [[NSMutableArray alloc] init];

EKAlarm *alarm1 = [EKAlarm alarmWithRelativeOffset:-[[itsAlertOne objectAtIndex:indexPath.row] intValue]]; // 1 Hour
// EKAlarm *alarm2 = [EKAlarm alarmWithRelativeOffset:-86400]; // 1 Day

[myAlarmsArray addObject:alarm1];
//[myAlarmsArray addObject:alarm2];

thisEvent.alarms = myAlarmsArray;
[myAlarmsArray release];

//setting the Reuccurence rule

NSString * test1 = [itsRecurrenceFrequency objectAtIndex:indexPath.row];

    BOOL isRecurrenceFrequencyExists = TRUE;

EKRecurrenceFrequency  recurrenceFrequency;

if ([test1 isEqualToString: @"EKRecurrenceFrequencyDaily"]) {
    recurrenceFrequency = EKRecurrenceFrequencyDaily;
}else if([test1 isEqualToString: @"EKRecurrenceFrequencyWeekly"]){
    recurrenceFrequency = EKRecurrenceFrequencyWeekly;
}else if([test1 isEqualToString: @"EKRecurrenceFrequencyMonthly"]){
    recurrenceFrequency = EKRecurrenceFrequencyMonthly;
}else if([test1 isEqualToString: @"EKRecurrenceFrequencyYearly"]){
    recurrenceFrequency = EKRecurrenceFrequencyYearly;
}else{
    isRecurrenceFrequencyExists = FALSE;
}

    if(isRecurrenceFrequencyExists){
        EKRecurrenceRule * recurrenceRule = [[EKRecurrenceRule alloc] 

                                     initRecurrenceWithFrequency:recurrenceFrequency
                                     interval:[[itsRecurrenceInterval objectAtIndex:indexPath.row]intValue]
                                     end:nil];
        if (thisEvent.endDate != nil) {
            EKRecurrenceEnd * end = [EKRecurrenceEnd recurrenceEndWithEndDate:thisEvent.endDate];
            recurrenceRule.recurrenceEnd = end;
        }else {
            thisEvent.endDate = thisEvent.startDate;
        }

        thisEvent.recurrenceRule = recurrenceRule;
        [recurrenceRule release];

    }
[thisEvent setCalendar:[eventStore defaultCalendarForNewEvents]];
NSError *err;


[eventStore saveEvent:thisEvent span:EKSpanFutureEvents error:&err]; 
NSLog(@"%@", thisEvent.eventIdentifier);
[self.eventsList addObject:thisEvent];

In this code I have the Event id of my calen开发者_运维百科dar event.

1. Now I want to update the event with the changes however Its not updating the previously created event.

2. Second I Need to know is it possible to capture the changes in calendar event they made in iPhone Calendar including deleting an event.

3. Can we delete the calendar event using the eventid?

Please help me if any one know the answer.. Thank you in advance.

Regards, Dilip Rajkumar

Event can be created by this:

[eventStore saveEvent:event span:EKSpanThisEvent error:&err]; 
   NSString* str = [[NSString alloc] initWithFormat:@"%@", event.eventIdentifier];
[arrayofCalIDs addObject:str];

You can delete the event using this:

EKEventStore* store = [[[EKEventStore alloc] init] autorelease];
   EKEvent* event2 = [store eventWithIdentifier:[arrayofCalIDs objectAtIndex:i]];
if (event2 != nil) {  
  NSError* error = nil;
  [store removeEvent:event2 span:EKSpanThisEvent error:&error];
} 
[myPath release];

For Updating Event you cannot directly access any method as it is not available in iOS. So, you can do one thing for this. 
(1) First remove the event with eventID.
(2) Create new Event using the same information of the last deleted event.