Sorting results from CoreData Fetch

In this case, you want to compare a CLLocation from the user to the lat & long you have on your CoreData:

NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];

NSEntityDescription *entity = [NSEntityDescription entityForName:ENTITY_NAME inManagedObjectContext:self.managedObjectContext]

[fetchRequest setEntity:entity];

NSArray *arrayOfEntities = [self.managedObjectContext executeFetchRequest:fetchRequest error:nil];

arrayOfEntities = [arrayOfEntities sortedArrayWithOptions:NSSortStable usingComparator:^NSComparisonResult(id obj1, id obj2)
    CLLocation *obj1EntityLocation = [[CLLocation alloc] initWithLatitude:[(NSNumber*)[obj1 valueForKey:ENTITY_LAT_KEY] doubleValue]longitude:[(NSNumber*)[obj1 valueForKey:ENTITY_LONG_KEY] doubleValue]];

    CLLocation *obj2EntityLocation = [[CLLocation alloc] initWithLatitude:[(NSNumber*)[obj2 valueForKey:ENTITY_LAT_KEY] doubleValue]longitude:[(NSNumber*)[obj2 valueForKey:ENTITY_LONG_KEY] doubleValue]];

    CLLocationDistance dist1 = [obj1EntityLocation distanceFromLocation:userLocation];
    CLLocationDistance dist2 = [obj2EntityLocation distanceFromLocation:userLocation];

    return [[NSNumber numberWithDouble:dist1] compare:[NSNumber numberWithDouble:dist2]];

return arrayOfEntities;

The point is to be able to sort an array that comes from CoreData in a nonlinear way, by using Blocks.

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