Receiving memory warning after saving 80 ekevents - ios

Question

- (void)syncWithCalendar
{
NSMutableDictionary *dictionary = [util readPListData];
NSMutableArray *courses = [util getCourses];
__block NSMutableArray *lessons;
__block NSMutableDictionary *lesson;
NSString *studentID = [util getProgramDetails].studentId;
NSString *programName = [util getProgramDetails].programName;
__block NSString *startDateString = #"", *endDateString = #"";
NSDateFormatter *formatter;
formatter = [[NSDateFormatter alloc] init];
[formatter setDateFormat:#"MM/dd/yyyy HH:mm:ss"];
[formatter setDateFormat:#"MM/dd/yyyy"];
NSString *currentDateString = [NSString stringWithFormat:#"%# 09:00:00", [formatter stringFromDate:[NSDate date]]];
[formatter setDateFormat:#"MM/dd/yyyy HH:mm:ss"];
NSDate *currentDate = [formatter dateFromString:currentDateString];
self.eventstore = [[EKEventStore alloc] init];
[self.eventstore requestAccessToEntityType:EKEntityTypeEvent completion:^(BOOL granted, NSError *error)
{
if (granted) {
NSLog(#"calendar access granted");
for (int i=0; i<[courses count]; i++)
{
lessons = [[courses objectAtIndex:i] objectForKey:#"lessons"];
for (int j=0; j<[lessons count]; j++)
{
lesson = [lessons objectAtIndex:j];
NSString *title = nil;
title = [NSString stringWithFormat:#"%# %#-Complete %# lesson",studentID,programName,[lesson objectForKey:#"lesson-name"]];
startDateString = [NSString stringWithFormat:#"%# %#", [lesson objectForKey:#"exam-date"], #"09:00:00"];
endDateString = [NSString stringWithFormat:#"%# %#", [lesson objectForKey:#"exam-date"], #"18:00:00"];
if (!([startDateString isEqualToString:#""] && [endDateString isEqualToString:#""]))
{
EKEvent *event = [EKEvent eventWithEventStore:self.eventstore];
event.title=title;
event.startDate = [formatter dateFromString:startDateString];
event.endDate = [formatter dateFromString:endDateString];
event.allDay = NO;
[event setCalendar:[self.eventstore defaultCalendarForNewEvents]];
NSError *err = nil;
[self.eventstore saveEvent:event span:EKSpanThisEvent commit:YES error:&err];
//[self.eventstore saveEvent:event span:EKSpanThisEvent error:&err];
if (err) {
NSLog(#"event not saved .. error = %#",err);
} else {
NSLog(#"event added successfully");
}
}
} // lessons for loop
} // courses for loop
} else {
NSLog(#"Access not granted");
}
}];
[self.eventstore release];
[formatter release];
}
After events gets successfully added it shows:
"Received Memory Warning. Terminating in response to SpringBoard's termination"
and the app terminates. This is happening in iOS 7 device. I haven't checked it yet in iOS 6 and below. The code works fine if there are only a few events saved (30 or less) but it shows memory issue for 80 events or more on saving.

Answer 1

Finally I found the answer to my question. I would like to share my solution so that it can help others ....
I was specially getting the crash in iOS 7 and it was because of the below line
// wrong
[self.eventstore saveEvent:event span:EKSpanThisEvent commit:YES error:&err];
The correct way to save event: (Note: I didn't require event identifier for my case)
// correct
[self.eventstore saveEvent:event span:EKSpanThisEvent commit:NO error:&err];
and then use
[self.eventstore commit:NULL]
after all the events are saved.
This stopped the crash in my case.

Answer 2

Switching to ARC may solve the problem with memory but problems may still occur with large amount of data.
Try using #autorelease pools inside for loop as in example
for (int i=0; i<[courses count]; i++)
{
#autoreleasepool {
lessons = [[courses objectAtIndex:i] objectForKey:#"lessons"];
for (int j=0; j<[lessons count]; j++)
{
lesson = [lessons objectAtIndex:j];
NSString *title = nil;
title = [NSString stringWithFormat:#"%# %#-Complete %# lesson",studentID,programName,[lesson objectForKey:#"lesson-name"]];
startDateString = [NSString stringWithFormat:#"%# %#", [lesson objectForKey:#"exam-date"], #"09:00:00"];
endDateString = [NSString stringWithFormat:#"%# %#", [lesson objectForKey:#"exam-date"], #"18:00:00"];
if (!([startDateString isEqualToString:#""] && [endDateString isEqualToString:#""]))
{
EKEvent *event = [EKEvent eventWithEventStore:self.eventstore];
event.title=title;
event.startDate = [formatter dateFromString:startDateString];
event.endDate = [formatter dateFromString:endDateString];
event.allDay = NO;
[event setCalendar:[self.eventstore defaultCalendarForNewEvents]];
NSError *err = nil;
[self.eventstore saveEvent:event span:EKSpanThisEvent commit:YES error:&err];
//[self.eventstore saveEvent:event span:EKSpanThisEvent error:&err];
if (err) {
NSLog(#"event not saved .. error = %#",err);
} else {
NSLog(#"event added successfully");
}
}
} // lessons for loop
}//autoreleasepool
} // courses for loop
This way each for loop step will release all autorelease objects.

Answer 3

#upendar I also have same scenario but i am split into small chunks, I.E. Like if you have 80 events to sync take 20-20 and pause 2-5sec. between them.
autoreleasepool is good to use, But it Calendar took too much memory to execute. It will take more then 100% some time.
I bared with this issue. Really interesting one!!!