• 模型一：LHLCar.h###

#import <Foundation/Foundation.h>

@interface LHLCar : NSObject

/**
 *  图标
 */
@property (nonatomic, copy)NSString *icon;
/**
 *  车名
 */
@property (nonatomic, copy)NSString *name;

+ (instancetype)carWithDict:(NSDictionary *)dict;
@end

• 模型一：LHLCar.m###

#import "LHLCar.h"

@implementation LHLCar

+ (instancetype)carWithDict:(NSDictionary *)dict{
    
    LHLCar *car = [[self alloc] init];
//    car.icon = dict[@"icon"];
//    car.name = dict[@"name"];
    [car setValuesForKeysWithDictionary:dict];
    return car;
}

@end

• 模型二：LHLCarGroups.h###

#import <Foundation/Foundation.h>

@interface LHLCarGroups : NSObject
/**
 *  车模型
 */
@property (nonatomic, strong) NSArray *cars;
/**
 *  标题 ABCD...
 */
@property (nonatomic, copy) NSString *title;

+ (instancetype)groupsWithDict:(NSDictionary *)dict;

@end

• 模型二：LHLCarGroups.m###

#import "LHLCarGroups.h"
#import "LHLCar.h"

@implementation LHLCarGroups

+ (instancetype)groupsWithDict:(NSDictionary *)dict{
    // 创建一个LHLCarGroups对象，用于接收dict传来的值
    LHLCarGroups *groups = [[self alloc] init];
    // 设置title
    groups.title = dict[@"title"];
    
    // 字典数组 -> 模型数组
    NSMutableArray *arrayM = [NSMutableArray array];
    for (NSDictionary *carDict in dict[@"cars"]) {
        [arrayM addObject:[LHLCar carWithDict:carDict]];
    }
    groups.cars = arrayM;
    return groups;
}
@end

• ViewController.m###

//
//  ViewController.m
//  20-索引条
//
//  Created by admin on 16/8/27.
//  Copyright © 2016年 admin. All rights reserved.
//

#import "ViewController.h"
#import "LHLCar.h"
#import "LHLCarGroups.h"

@interface ViewController ()

@property (nonatomic, strong) NSArray *carGroups;

@end

@implementation ViewController
/**
 *  懒加载
 */
- (NSArray *)carGroups{
    if (_carGroups == nil) {
        // 加载plist文件
        NSArray *carDict = [NSArray arrayWithContentsOfFile:[[NSBundle mainBundle] pathForResource:@"cars.plist" ofType:nil]];
        
        // 字典模型 －> 数组模型
        NSMutableArray *arrayM = [NSMutableArray array];
        for (NSDictionary *groupsDict in carDict) {
            [arrayM addObject:[LHLCarGroups groupsWithDict:groupsDict]];
        }
        _carGroups = arrayM;
    }
    return _carGroups;
}

- (void)viewDidLoad {
    [super viewDidLoad];

    // 设置索引条文字颜色
    self.tableView.sectionIndexColor = [UIColor redColor];
    // 设置索引条背景颜色
    self.tableView.sectionIndexBackgroundColor = [UIColor grayColor];
}

/**
 *  隐藏状态栏
 */
- (BOOL) prefersStatusBarHidden{
    return YES;
}
#pragma mark - 数据源方法
/**
 *  有多少个分组
 */
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView{

    return self.carGroups.count;
}
/**
 *  每一组有多少行
 */
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{
    LHLCarGroups *groups = self.carGroups[section];
    return groups.cars.count;
}
/**
 *  单元格
 */
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
    
    static NSString *ID = @"Car";
    // 在缓存池中通过ID查找可重用的单元格
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:ID];
    // 如果没有找到 则创建一个cell
    if (cell == nil) {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:ID];
    }
    // 设置数据
//    NSLog(@"%@",_carGroups);
    LHLCarGroups *groups = self.carGroups[indexPath.section];
    LHLCar *car = groups.cars[indexPath.row];
    cell.imageView.image = [UIImage imageNamed:car.icon];
    cell.textLabel.text = car.name;
    
    return cell;
}
/**
 *  设置表格的title
 */
- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section{
    LHLCarGroups *groups = self.carGroups[section];
    return groups.title;
}

/**
 *  索引条
 */
- (NSArray<NSString *> *)sectionIndexTitlesForTableView:(UITableView *)tableView{
//    NSMutableArray *arrayM = [NSMutableArray array];
//    for (LHLCarGroups *groups in self.carGroups) {
//        [arrayM addObject:groups.title];
//    }
//    return arrayM;
    
   // KVC取值
    return [self.carGroups valueForKeyPath:@"title"];
}
@end