Diferencia en horas entre dos NSDate
Aquí estoy tratando de calcular las horas entre dos fechas. Cuando ejecuto la aplicación, se bloquea. ¿Podría por favor decirme el error en este código?
<code>NSString *lastViewedString = @"2012-04-25 06:13:21 +0000"; NSDateFormatter *dateFormatter = [[[NSDateFormatter alloc] init] autorelease]; [dateFormatter setDateFormat: @"yyyy-MM-dd HH:mm:ss zzz"]; NSDate *lastViewed = [[dateFormatter dateFromString:lastViewedString] retain]; NSDate *now = [NSDate date]; NSLog(@"lastViewed: %@", lastViewed); //2012-04-25 06:13:21 +0000 NSLog(@"now: %@", now); //2012-04-25 07:00:30 +0000 NSTimeInterval distanceBetweenDates = [now timeIntervalSinceDate:lastViewed]; double secondsInAnHour = 3600; NSInteger hoursBetweenDates = distanceBetweenDates / secondsInAnHour; NSLog(@"hoursBetweenDates: %@", hoursBetweenDates); </code>