Brief Description
Use NSCalendar method:
(NSDateComponents *)components:(NSUInteger)unitFlags fromDate:(NSDate *)startingDate toDate:(NSDate *)resultDate options:(NSUInteger)opts
"Returns, as an NSDateComponents object using specified components, the difference between two supplied dates". From the API documentation.
Create 2 NSDate whose difference is the NSTimeInterval you want to convert. (If your NSTimeInterval comes from comparing 2 NSDate you don't need to do this step, and you don't even need the NSTimeInterval).
Get your quotes from NSDateComponents
Sample Code
// The time interval
NSTimeInterval theTimeInterval = 326.4;
// Get the system calendar
NSCalendar *sysCalendar = [NSCalendar currentCalendar];
// Create the NSDates
NSDate *date1 = [[NSDate alloc] init];
NSDate *date2 = [[NSDate alloc] initWithTimeInterval:theTimeInterval sinceDate:date1];
// Get conversion to months, days, hours, minutes
unsigned int unitFlags = NSHourCalendarUnit | NSMinuteCalendarUnit | NSDayCalendarUnit | NSMonthCalendarUnit;
NSDateComponents *conversionInfo = [sysCalendar components:unitFlags fromDate:date1 toDate:date2 options:0];
NSLog(@"Conversion: %dmin %dhours %ddays %dmoths",[conversionInfo minute], [conversionInfo hour], [conversionInfo day], [conversionInfo month]);
[date1 release];
[date2 release];
Known issues