[iOS基础控件 - 6.4] 汽车品牌展示 Model嵌套/KVC/TableView索引

A.需求

1.使用汽车品牌名称头字母为一个Model，汽车品牌为一个Model，头字母Model嵌套品牌Model

2.使用KVC进行Model封装赋值

3.展示头字母标题

4.展示索引（使用KVC代替遍历取出所有索引值）

B.实现

1.Model嵌套

其实就是将另一个Model作为成员

.plist 文件结构

GroupCar中有存储Car的数组

1 @property(nonatomic, strong) NSArray *cars;

封装Model的时候需要进行相应处理

CarGroup.m

1         // 这里不能用KVC，封装car model再放到array中，不能直接存储array
2         NSArray *carsArray = dictionary[@"cars"];
3         NSMutableArray *mcarsArray = [NSMutableArray array];
4         for (NSDictionary *dict in carsArray) {
5             Car *car = [Car carWithDictionary:dict];
6             [mcarsArray addObject:car];
7         }
8
9         self.cars = mcarsArray;

2.KVC

成员名使用和从dictionary取出来的键名一致，从而能用一个方法赋值所有成员属性，所见代码量

 1 Car.m
 2 - (instancetype) initWithDictionary:(NSDictionary *) dictionary {
 3     if (self = [super init]) {
 4         // 当dictionary中的键名跟Model中的成员名一致的时候，可以使用KVC
 5         [self setValuesForKeysWithDictionary:dictionary];
 6
 7 //        self.icon = dictionary[@"icon"];
 8 //        self.name = dictionary[@"name"];
 9     }
10
11     return self;
12 }
13  

3.展示标题 setTitle

1 /** 设置section头部标题 */
2 - (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section

4.索引

1 /** 索引 */
2 - (NSArray *)sectionIndexTitlesForTableView:(UITableView *)tableView {
3     // 使用KVC取出数组，不用使用遍历封装
4     return [self.carGroups valueForKey:@"title"];
5 }

C.主要代码

 1 //
 2 //  Car.h
 3 //  CarGroup
 4 //
 5 //  Created by hellovoidworld on 14/12/2.
 6 //  Copyright (c) 2014年 hellovoidworld. All rights reserved.
 7 //
 8
 9 #import <Foundation/Foundation.h>
10
11 @interface Car : NSObject
12
13 @property(nonatomic, copy) NSString *icon;
14 @property(nonatomic, copy) NSString *name;
15
16 - (instancetype) initWithDictionary:(NSDictionary *) dictionary;
17 + (instancetype) carWithDictionary:(NSDictionary *) dictionary;
18 + (instancetype) car;
19
20 @end

 1 //
 2 //  Car.m
 3 //  CarGroup
 4 //
 5 //  Created by hellovoidworld on 14/12/2.
 6 //  Copyright (c) 2014年 hellovoidworld. All rights reserved.
 7 //
 8
 9 #import "Car.h"
10
11 @implementation Car
12
13 - (instancetype) initWithDictionary:(NSDictionary *) dictionary {
14     if (self = [super init]) {
15         // 当dictionary中的键名跟Model中的成员名一致的时候，可以使用KVC
16         [self setValuesForKeysWithDictionary:dictionary];
17
18 //        self.icon = dictionary[@"icon"];
19 //        self.name = dictionary[@"name"];
20     }
21
22     return self;
23 }
24
25 + (instancetype) carWithDictionary:(NSDictionary *) dictionary {
26     return [[self alloc] initWithDictionary:dictionary];
27 }
28
29 + (instancetype) car {
30     return [self carWithDictionary:nil];
31 }
32
33 @end

 1 //
 2 //  CarGroup.h
 3 //  CarGroup
 4 //
 5 //  Created by hellovoidworld on 14/12/2.
 6 //  Copyright (c) 2014年 hellovoidworld. All rights reserved.
 7 //
 8
 9 #import <Foundation/Foundation.h>
10
11 @interface CarGroup : NSObject
12
13 @property(nonatomic, strong) NSArray *cars;
14 @property(nonatomic, copy) NSString *title;
15
16 - (instancetype) initWithDictionary:(NSDictionary *) dictionary;
17 + (instancetype) carGroupWithDictionary:(NSDictionary *) dictionary;
18 + (instancetype) carGroup;
19
20 @end

 1 //
 2 //  CarGroup.m
 3 //  CarGroup
 4 //
 5 //  Created by hellovoidworld on 14/12/2.
 6 //  Copyright (c) 2014年 hellovoidworld. All rights reserved.
 7 //
 8
 9 #import "CarGroup.h"
10 #import "Car.h"
11
12 @implementation CarGroup
13
14 - (instancetype) initWithDictionary:(NSDictionary *) dictionary {
15     if (self = [super init]) {
16         self.title = dictionary[@"title"];
17
18         // 这里不能用KVC，封装car model再放到array中，不能直接存储array
19         NSArray *carsArray = dictionary[@"cars"];
20         NSMutableArray *mcarsArray = [NSMutableArray array];
21         for (NSDictionary *dict in carsArray) {
22             Car *car = [Car carWithDictionary:dict];
23             [mcarsArray addObject:car];
24         }
25
26         self.cars = mcarsArray;
27     }
28
29     return self;
30 }
31
32 + (instancetype) carGroupWithDictionary:(NSDictionary *) dictionary {
33     return [[self alloc] initWithDictionary:dictionary];
34 }
35
36 + (instancetype) carGroup {
37     return [self carGroupWithDictionary:nil];
38 }
39
40 @end

 1 //
 2 //  ViewController.m
 3 //  CarGroup
 4 //
 5 //  Created by hellovoidworld on 14/12/1.
 6 //  Copyright (c) 2014年 hellovoidworld. All rights reserved.
 7 //
 8
 9 #import "ViewController.h"
10 #import "CarGroup.h"
11 #import "Car.h"
12
13 @interface ViewController () <UITableViewDataSource>
14 @property (weak, nonatomic) IBOutlet UITableView *tableView;
15
16 // 所有的车品牌
17 @property(nonatomic, strong) NSArray *carGroups;
18
19 @end