排序字典对象的数组

时间:2012-11-13 12:24:11

标签: iphone ios xcode nsmutablearray

我遇到的问题是我无法排序NSMutableArray的NSMutableDictionary对象,我想通过评级对对象进行排序,评级是NSNumber,我缺少什么?

我当前的代码总结了“arrayMealRating”中的所有评级,并对生成的数组进行排序:

            [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];

有任何疑问,请不要投票,只要问,我会编辑问题。

最好的问候,对不起我的英语不好。

1 个答案:

答案 0 :(得分:4)

这应该做你想要的:

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