Forming NSString "2012-06-29" into NSDate's "NSDateFormatterMediumStyle"?

I'm trying to separate the month and day from the following string.

2012-06-29
 

I've tried formatting the string into the medium style by doing the following:

//Setting Up My Formatter
 formatter = [[NSDateFormatter alloc] init];
 [formatter setDateStyle:NSDateFormatterMediumStyle];
 [formatter setTimeStyle:NSDateFormatterShortStyle];
 
 Forming String Into Formatted Date
 NSDate *dateFromString = [formatter dateFromString:event.date];
 
 //Separating Components
 NSDateComponents *components = [[NSCalendar currentCalendar] components:NSDayCalendarUnit | NSMonthCalendarUnit | NSYearCalendarUnit fromDate:dateFromString];
 
 //Assigning Each Component to my Cell's Labels
 cell.dayLabel.text = [NSString stringWithFormat:@"%d", [components day]];
 cell.monthLabel.text = [NSString stringWithFormat:@"%d", [components month]];
 

When I ran the NSLogs my "event.date" came back "2012-06-26 & dateFromString came back null. Can anyone help guide my in the right direction? Thanks a lot!

EDIT:

So I finally figured out from your help that I was setting the format incorrectly. Instead of using:

[formatter setDateStyle:NSDateFormatterMediumStyle];
 

I am now using:

[formatter setDateFormat:@"yyyy-MM-dd"];
 

Here is my question though, from the components, the month is coming back as an integer (1, 2, 3) but I want it to come back as "MMM" (Jan, Feb, Mar). Thanks!

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