Question

the problem im having is that i cant sort an NSMutableArray of NSMutableDictionary Objects, I want to sort the objects by rating, the rating is a NSNumber, what am i missing?

My current code that sums all the ratings from “arrayMealRating” and sorts the resulting array:

            [arrayMealRating addObject:[NSMutableDictionary dictionaryWithObjectsAndKeys:
                                        [eachObject objectForKey:@"Airline"], @"Airline"
                                        ,[eachObject objectForKey:@"setMealRating"], @"setMealRating"
                                        , nil]];

        }
        NSArray *airlineNames = [arrayMealRating valueForKeyPath:@"@distinctUnionOfObjects.Airline"];

        // Loop through all the airlines
        for (NSString *airline in airlineNames) {

            // Get an array of all the dictionaries for the current airline
            NSPredicate *predicate = [NSPredicate predicateWithFormat:@"(Airline == %@)", airline];
            NSArray *airlineMealRating = [arrayMealRating filteredArrayUsingPredicate:predicate];

            // Get the sum of all the ratings using KVC @sum collection operator
            NSNumber *rating = [airlineMealRating valueForKeyPath:@"@sum.setMealRating"];

            //NSLog(@"%@: %@", airline, rating);
            [sortedMealArray addObject:[NSMutableDictionary dictionaryWithObjectsAndKeys:
                                        airline, @"Airline"
                                        ,[rating stringValue], @"setMealRating"
                                      , nil]];
        }



        NSSortDescriptor *descriptor = [[NSSortDescriptor alloc] initWithKey:@"setMealRating"  ascending:YES];
        [sortedMealArray sortedArrayUsingDescriptors:[NSMutableArray arrayWithObjects:descriptor,nil]];
        auxMealRating = [sortedMealArray copy];

Any doubt, please dont down vote, just ask and i will edit the question.

Best Regards and sorry for my poor english.

Answer 1

This should do what you want:

NSArray *sortedArray = [arrayMealRating sortedArrayUsingComparator:^(id obj1, id obj2) {
    NSNumber *rating1 = [(NSDictionary *)obj1 objectForKey:@"setMealRating"];
    NSNumber *rating2 = [(NSDictionary *)obj2 objectForKey:@"setMealRating"];
    return [rating1 compare:rating2];
}];