ios - 如何将 NSMutableDictionary setObject 的值赋值成为 indexPath.section 的值？

Question

我有 NSMutableDictionary 并返回结果如下:-

NSMutableDictionary *result = [NSMutableDictionary new];
        distinctNames = [_aryClippedCategoryList valueForKeyPath:@"@distinctUnionOfObjects.category_id"];
        for (NSString *category_id in distinctNames) {
            NSPredicate *predicate = [NSPredicate predicateWithFormat:@"category_id = %@", category_id];
            NSArray *category_group = [_aryClippedCategoryList filteredArrayUsingPredicate:predicate];
            [result setObject:category_group forKey:category_id];

NSLog(@"123 - %@", result); 
NSLog(@"223 - %lu", (unsigned long)distinctNames.count); 

在 NSLog 123 中，结果将如下所示:-

 17 =     (
                {
            "category_id" = 17;
            "category_name" = "Apparel & Accessories";
            "sub_category_id" = 17;
            "sub_category_name" = "Fashion jewelry";
        },
                {
            "category_id" = 17;
            "category_name" = "Apparel & Accessories";
            "sub_category_id" = 16;
            "sub_category_name" = Wholesale;
        }   
    );
    20 =     (
                {
            "category_id" = 20;
            "category_name" = "Beauty & Personal Care";
             "sub_category_id" = 288;
            "sub_category_name" = "Pedicure & medicure";
        },
                {
            "category_id" = 20;
            "category_name" = "Beauty & Personal Care";
            "sub_category_id" = 285;
            "sub_category_name" = "Fragrances and perfumes";
        }
);

在 NSLog 223 中，结果将如下所示:-

223 - 2

在这种情况下，如何在 CollectionView 中选择 category_group 作为部分值并在 CollectionView 单元格中显示每组项目(category_id、category_name、sub_category_id、sub_category_name)？

Answer 1

• (不推荐)您应该使用 NSMutableArray 而不是 NSMutableDictionary。

  结构是

  Array<Dictionary<Array *> *> *
  

  代码是这样的

  NSMutableArray *groups = [NSMutableArray new];
  <# your code #>
  [groups addObject:@{
      @"category_id": category_id,
      @"infos": category_group
  }];
  

  然后

  NSString *groupID = groups[indexPath.section][@"category_id"]
  

  这是您需要的部分的组值。

  NSArray *infos = groups[indexPath.section][@"infos"];
  NSDictionary *info = infos[indexPath.item];
  

  这是对象dict元素值(value)

• (推荐)或改变您的data到 object . (对象NSMutableArray<Object *> *)

  然后使用groups.count获取部分。

  groups[indexPath.section].categoryID
  

  这是您需要的 sections 的组值.

  group = groups[indexPath.section]
  object = group.infos[indexPath.item]
  

  这是 items 的对象值