iOS 数据列表根据字母排序

注：本文是根据数据模型WECompanyModel的某个属性firstLetter进行排序

一、首先设置一个索引属性

@property (nonatomic, strong) UILocalizedIndexedCollation *collation;

二、设置右侧字母索引的背景和颜色

self.tableView.sectionIndexColor = RGBAlphaColorValue(0x999999);
self.tableView.sectionIndexBackgroundColor = [UIColor clearColor];
self.tableView.sectionIndexTrackingBackgroundColor = RGBAlphaColorValue(0xf3f3f3);

三、设置分组字母索引的数据源和代理

// 设置section的Header
- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section {
    NSArray *userObjsInSection = [_dataArray objectAtIndex:section];
    if(userObjsInSection == nil || [userObjsInSection count] <= 0) {
        return nil;
    }
    return [[_collation sectionTitles] objectAtIndex:section];
}
// 设置索引标题
- (NSArray *)sectionIndexTitlesForTableView:(UITableView *)tableView {
    return [_collation sectionIndexTitles];
}
// 关联搜索
- (NSInteger)tableView:(UITableView *)tableView sectionForSectionIndexTitle:(NSString *)title atIndex:(NSInteger)index {
    return [_collation sectionForSectionIndexTitleAtIndex:index];
}

四、网络请求列表，将列表数据数组内容进行排序

#pragma mark - Request
- (void)requestDatas {
    NSString *path = [NSString stringWithFormat:@"label/cfcp/%@",@(self.pid)];
    [WEHttpRequest requestWithConfig:^(WEUrlRequestConfig *request) {
        request.baseUrl = HostUrl;
        request.url = path;
        request.methodType = WEHttpMethodGET;
        request.timeoutInterval = 15;
        request.parameters = self.params;
        [request setValue:[WELoginManager sharedInstance].accessToken forHeaderField:kAccessToken];
    } success:^(NSDictionary *responseObject) {
        [WEHUD hideHUD];
        NSArray *dataArray = [NSArray array];
        dataArray = responseObject[@"data"];
        [self.dataArray removeAllObjects];
        if (dataArray.count > 0) {
            NSArray *tempArray = [NSArray modelArrayWithClass:WECompanyModel.class json:dataArray];
            //获得当前UILocalizedIndexedCollation对象并且引用赋给collation,A-Z的数据
            self.collation = [UILocalizedIndexedCollation currentCollation];
            //获得索引数和section标题数
            NSInteger index, sectionTitlesCount = [[_collation sectionTitles] count];
            //临时数据，存放section对应的userObjs数组数据
            NSMutableArray *newSectionsArray = [[NSMutableArray alloc] initWithCapacity:sectionTitlesCount];
            //设置sections数组初始化：元素包含userObjs数据的空数据
            for (index = 0; index < sectionTitlesCount; index++) {
                NSMutableArray *array = [[NSMutableArray alloc] init];
                [newSectionsArray addObject:array];
            }
            //将用户数据进行分类，存储到对应的sesion数组中
            for (WECompanyModel *model in tempArray) {
                //根据timezone的localename，获得对应的的section number
                NSInteger sectionNumber = [_collation sectionForObject:model collationStringSelector:@selector(firstLetter)];// 根据WECompanyModel模型的字段属性firstLetter进行排序，也可根据name属性进行排序，排序可能花费时间较长
                //获得section的数组
                NSMutableArray *sectionUserObjs = [newSectionsArray objectAtIndex:sectionNumber];
                //添加内容到section中
                [sectionUserObjs addObject:model];
            }
            //排序，对每个已经分类的数组中的数据进行排序，如果仅仅只是分类的话可以不用这步
            for (index = 0; index < sectionTitlesCount; index++) {
                NSMutableArray *userObjsArrayForSection = [newSectionsArray objectAtIndex:index];
                //获得排序结果，根据模型的firstLetter字段进行排序
                NSArray *sortedUserObjsArrayForSection = [_collation sortedArrayFromArray:userObjsArrayForSection collationStringSelector:@selector(firstLetter)];
                //替换原来数组
                [newSectionsArray replaceObjectAtIndex:index withObject:sortedUserObjsArrayForSection];
            }
            self.dataArray = newSectionsArray;
            [self.tableView reloadData];
            [self.tableView.mj_header endRefreshing];
        } else {
            [self.dataArray removeAllObjects];
            [self.tableView reloadData];
            [self.tableView.mj_header endRefreshing];
        }
    } failed:^(NSError *error) {
        debugMethod();
    }];
}