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You want to sort the managed objects (records) that you fetch from a managed object context (database).
Create instances of NSSortDescriptor for
each attribute (column, in the database world) of an entity that has
to be sorted. Add the sort descriptors to an array and assign the
array to an instance of NSFetchRequest using
the setSortDescriptors:
instance method. In this example code, Sorting_Data_in_Core_DataAppDelegate is the
class that represents the app delegate in a universal app. To
understand how the Person entity is
created, please refer to Recipes 13.1 and 13.2:
- (BOOL) application:(UIApplication *)application
didFinishLaunchingWithOptions:(NSDictionary *)launchOptions{
[self createNewPersonWithFirstName:@"Richard"
lastName:@"Branson"
age:61];
[self createNewPersonWithFirstName:@"Anthony"
lastName:@"Robbins"
age:51];
/* Create the fetch request first */
NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
/* Here is the entity whose contents we want to read */
NSEntityDescription *entity =
[NSEntityDescription entityForName:@"Person"
inManagedObjectContext:self.managedObjectContext];
NSSortDescriptor *ageSort =
[[NSSor....