EKCalendarChooser crashes on iOS11.1 - ios11

Question

I execute the following code to let the user choose multiple calendars to use for my notepad app. Until iOS 10.3.1, there was no problem. On 11.0.2, it was still working on actural devices. However, since 11.1 it crashes with the following error.
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[__NSDictionaryM setObject:forKeyedSubscript:]: key cannot be nil'
The code is as follows. Basically, I'm opening a blank calendar chooser.
if (_eventStore == nil) {
_eventStore = [[EKEventStore alloc] init];
}
// the selector is available, so we must be on iOS 6 or newer
[_eventStore requestAccessToEntityType:EKEntityTypeEvent
completion:^(BOOL granted, NSError *error) {
dispatch_async(dispatch_get_main_queue(), ^{
if (error)
{
// display error message here
}
else if (!granted)
{
// display access denied error message here
}
else
{
// access granted
EKCalendarChooser *calendarChooser = [[EKCalendarChooser alloc]
initWithSelectionStyle:EKCalendarChooserSelectionStyleMultiple
displayStyle:EKCalendarChooserDisplayAllCalendars
eventStore:_eventStore];
calendarChooser.modalTransitionStyle = UIModalTransitionStyleCoverVertical;
calendarChooser.delegate = self;
calendarChooser.showsCancelButton = YES;
calendarChooser.showsDoneButton = YES;
NSSet *calendarSet = [[NSSet alloc] init];
calendarChooser.selectedCalendars = calendarSet;
UINavigationController *sub = [[UINavigationController alloc] initWithRootViewController:calendarChooser];
sub.navigationBar.barStyle = UIBarStyleDefault;
sub.toolbar.barStyle = UIBarStyleDefault;
[self presentViewController:sub animated:YES completion:nil];
//ios11 crashes after this
}
});
}];
Thanks for your help.

Answer 1

It turns out that EKCalendarChooserDisplayAllCalendars was causing the crash. Although it's not ideal, now I can avoid the crash when iOS is 11.1 or higher.
EKCalendarChooserDisplayStyle displayStyle = EKCalendarChooserDisplayAllCalendars;
if (#available(iOS 11.1, *)) {
displayStyle = EKCalendarChooserDisplayWritableCalendarsOnly;
}
EKCalendarChooser *calendarChooser = [[EKCalendarChooser alloc]
initWithSelectionStyle:EKCalendarChooserSelectionStyleMultiple
displayStyle:displayStyle
eventStore:eventStore];