在介绍小项目之前，在此说明一下此代码并非本人所写，我只是随笔的整理者。

在介绍之前先展现一下效果图。

看过效果图大家应该很熟悉了，就是饿了么的一个界面而已，值得注意的是，实现时并没有采用本地连接，而是实打实的网络连接。看一下文件架构。

这一采用的是MVC设计模式，虽然文件很少，但是也可以看。

下面开始正式介绍小项目的实现。

首先介绍Model的实现，很简单，实现模型即可，

Shop.h

////  Shop.h//  CX－小项目（饿了么 网络部分 简单实现）////  Created by ma c on 16/3/23.//  Copyright © 2016年 xubaoaichiyu. All rights reserved.//#import 
     
      @interface Shop : NSObject//建立Shop模型@property (nonatomic, copy) NSString * address;@property (nonatomic, copy) NSString * name;@property (nonatomic, copy) NSString * image_path;//-description这个方法系统占用@property (nonatomic, copy) NSString * desc;@end
     

 Shop.m

////  Shop.m//  CX－小项目（饿了么 网络部分 简单实现）////  Created by ma c on 16/3/23.//  Copyright © 2016年 xubaoaichiyu. All rights reserved.//#import "Shop.h"@implementation Shop@end

model实现后我们并没有真正的实现方法，下面也不是，接下来是对AFN的封装，之所以封装是因为，我们难以保证在以后该三方还能存在，只要封装，哪怕以后没有了AFN我们也可以在封装框架里运用其他的三方实现。

HttpClient.h HttpClient.m

////  HttpClient.h//  CX－小项目（饿了么 网络部分 简单实现）////  Created by ma c on 16/3/23.//  Copyright © 2016年 xubaoaichiyu. All rights reserved.//#import 
     
      #import "AFNetworking.h"//HTTP请求类别typedef NS_ENUM(NSInteger,HttpRequestType) {    HttpRequestGet,    HttpRequestPost,    HttpRequestPut,    HttpRequestDelete,};/** *  请求前预处理block */typedef void(^PrepareExecuteBlock)(void);typedef void(^SuccessBlock)(NSURLSessionDataTask * task, id responseObject);typedef void(^FailureBlock)(NSURLSessionDataTask * task, NSError * error);@interface HttpClient : NSObject+ (HttpClient *)defaultClient;/** *  HTTP请求（GET,POST,PUT,DELETE） * *  @param url     请求地址 *  @param method  请求类型 *  @param params  请求参数 *  @param prepare 请求前预处理 *  @param success 请求成功处理 *  @param failure 请求失败处理 */- (void)requestWithPath:(NSString *)url                 method:(NSInteger)method            paramenters:(NSDictionary *)params         prepareExecute:(PrepareExecuteBlock)prepare                success:(SuccessBlock)success                failure:(FailureBlock)failure;@end
     

////  HttpClient.m//  CX－小项目（饿了么 网络部分 简单实现）////  Created by ma c on 16/3/23.//  Copyright © 2016年 xubaoaichiyu. All rights reserved.//#import "HttpClient.h"@interface HttpClient ()@property (nonatomic, strong) AFHTTPSessionManager * manager;@property (nonatomic, assign) BOOL isConnect;@end@implementation HttpClient- (instancetype)init{    self = [super init];    if (self) {                self.manager = [AFHTTPSessionManager manager];        //设置请求类型        self.manager.requestSerializer = [AFHTTPRequestSerializer serializer];        //设置响应类型        self.manager.responseSerializer = [AFJSONResponseSerializer serializer];                self.manager.responseSerializer.acceptableContentTypes = [NSSet setWithObjects:@"application/json",@"text/html", @"text/json", @"text/javascript",@"text/plain",@"image/gif", nil];                //开启监听        [self openNetMonitoring];            }    return self;}//判断是否有网络连接，有网络连接再进行下一操作。- (void)openNetMonitoring {        [[AFNetworkReachabilityManager sharedManager] setReachabilityStatusChangeBlock:^(AFNetworkReachabilityStatus status) {                switch (status) {            case AFNetworkReachabilityStatusUnknown:                self.isConnect = NO;                break;            case AFNetworkReachabilityStatusNotReachable:                self.isConnect = NO;                break;            case AFNetworkReachabilityStatusReachableViaWiFi:                self.isConnect = YES;                break;            case AFNetworkReachabilityStatusReachableViaWWAN:                self.isConnect = YES;                break;            default:                break;        }            }];        [[AFNetworkReachabilityManager sharedManager] startMonitoring];        self.isConnect = YES;}//单例+ (HttpClient *)defaultClient {        static HttpClient * instance = nil;    static dispatch_once_t onceToken;    dispatch_once(&onceToken, ^{        instance = [[self alloc] init];    });    return instance;}- (void)requestWithPath:(NSString *)url                 method:(NSInteger)method            paramenters:(NSDictionary *)params         prepareExecute:(PrepareExecuteBlock)prepare                success:(SuccessBlock)success                failure:(FailureBlock)failure {            if ([self isConnectionAvailable]) {                //预处理        if (prepare) {            prepare();        }                switch (method) {            case HttpRequestGet:                [self.manager GET:url parameters:params progress:nil success:success failure:failure];                break;            case HttpRequestPost:                [self.manager POST:url parameters:params progress:nil success:success failure:failure];                break;            case HttpRequestPut:                [self.manager PUT:url parameters:params success:success failure:failure];                break;            case HttpRequestDelete:                [self.manager DELETE:url parameters:params success:success failure:failure];                break;            default:                break;        }            } else {                [self showExceptionDialog];    }}- (BOOL)isConnectionAvailable {        return self.isConnect;}//如果，没有网络，弹出Alert- (void)showExceptionDialog {        [[[UIAlertView alloc] initWithTitle:@"提示" message:@"网络连接异常，请检查网络连接" delegate:nil cancelButtonTitle:@"好的" otherButtonTitles: nil] show];}@end

接下来是对SVProgressHUD进行封装

TollHeper.h TollHeper.m

////  ToolHelper.h//  CX－小项目（饿了么 网络部分 简单实现）////  Created by ma c on 16/3/23.//  Copyright © 2016年 xubaoaichiyu. All rights reserved.//#import 
     
      @interface ToolHelper : NSObject/******************* 指示器方法  ****************///对指示器进行封装，如可出现新的主流三方，可以很好的给予升级//弹出操作错误信息提示框+ (void)showErrorMessage:(NSString *)message;//弹出操作成功信息提示框+ (void)showSuccessMessage:(NSString *)message;//弹出加载提示框+ (void)showProgressMessage:(NSString *)message;//弹出用户信息+ (void)showInfoMessage:(NSString *)message;//取消弹出框+ (void)dismissHUD;@end
     

////  ToolHelper.m//  CX－小项目（饿了么 网络部分 简单实现）////  Created by ma c on 16/3/23.//  Copyright © 2016年 xubaoaichiyu. All rights reserved.//#import "ToolHelper.h"#import "SVProgressHUD.h"@implementation ToolHelper//弹出操作错误信息提示框+ (void)showErrorMessage:(NSString *)message {        [SVProgressHUD showErrorWithStatus:message];    }//弹出操作成功信息提示框+ (void)showSuccessMessage:(NSString *)message {        [SVProgressHUD showSuccessWithStatus:message];}//弹出加载提示框+ (void)showProgressMessage:(NSString *)message {        [SVProgressHUD showWithStatus:message];    }//弹出用户信息+ (void)showInfoMessage:(NSString *)message {        [SVProgressHUD showInfoWithStatus:message];    }//取消弹出框+ (void)dismissHUD {        [SVProgressHUD dismiss];}@end

做完以上工作之后下面需要解决的便是上面遗留下来的问题，不知道大家有没有发现在model里的注释

//-description这个方法系统占用

 我们该怎么解决这个问题呢，那么我要说的便是三方啦。

MJ的三方解决了这一问题

MJExtensionConfig.h MJExtensionConfig.m

////  MJExtensionConfig.h//  CX－小项目（饿了么 网络部分 简单实现）////  Created by ma c on 16/3/23.//  Copyright © 2016年 xubaoaichiyu. All rights reserved.//#import 
     
      @interface MJExtensionConfig : NSObject@end
     

////  MJExtensionConfig.m//  CX－小项目（饿了么 网络部分 简单实现）////  Created by ma c on 16/3/23.//  Copyright © 2016年 xubaoaichiyu. All rights reserved.//#import "MJExtensionConfig.h"#import "MJExtension.h"#import "Shop.h"@implementation MJExtensionConfig//程序启动一定会调用+ (void)load {        /**     *  解决网络的JSON字段和本地模型属性名不一致的情况     *     *  @return 左边是本地属性名，右侧是网络JSON名     */        [Shop mj_setupReplacedKeyFromPropertyName:^NSDictionary *{                return @{@"desc" : @"description"};    }];    }@end

（对于load在前面的博客我有详细的解释，不清楚的朋友可以看看）

处理过后，为了方便对整个程序都能用到的便俩个 头文件进行优化，我们采用PCH文件

ELeMe.pch

////  ELeMe.pch//  CX－小项目（饿了么 网络部分 简单实现）////  Created by ma c on 16/3/23.//  Copyright © 2016年 xubaoaichiyu. All rights reserved.//#ifndef ELeMe_pch#define ELeMe_pch#ifdef __OBJC__#import 
     
      #import 
      
       #endif#import "ToolHelper.h"/***************SERVER HOST***************/#define SERVER_HOST @"http://restapi.ele.me/v3"/***************SERVER API***************///获取餐馆列表#define API_GetRestaurantsList @"/restaurants"#define SCREEN_WIDTH [UIScreen mainScreen].bounds.size.width#define SCREEN_HEIGHT [UIScreen mainScreen].bounds.size.height#define shopInfoPageLimit 20#endif /* ELeMe_pch */
      
     

写完代码我们需要设置一下

设置如下

 

其实整个小项目真的很简单，导致并没有什么可以仔细去想的，写多了就好了。

下面是主要环节（注释说明的很详尽了，我就不多说废话了）

ViewController.h ViewController.m

////  ViewController.h//  CX－小项目（饿了么 网络部分 简单实现）////  Created by ma c on 16/3/23.//  Copyright © 2016年 xubaoaichiyu. All rights reserved.//#import 
     
      @interface ViewController : UIViewController@end
     

////  ViewController.m//  CX－小项目（饿了么 网络部分 简单实现）////  Created by ma c on 16/3/23.//  Copyright © 2016年 xubaoaichiyu. All rights reserved.//#import "ViewController.h"#import "HttpClient.h"#import "SVProgressHUD.h"#import "Shop.h"#import "MJExtension.h"#import "ShopIconCell.h"#import "MJRefresh.h"static NSString * identifier = @"ShopInfoCell";@interface ViewController ()
     
      //分页的页数@property (nonatomic, assign) NSInteger page;@property (nonatomic, strong) UITableView * tableView;@property (nonatomic, strong) NSMutableArray * dataList;@end@implementation ViewController- (NSMutableArray *)dataList {        if (!_dataList) {        _dataList = [NSMutableArray array];    }    return _dataList;}- (UITableView *)tableView {        if (!_tableView) {        _tableView = [[UITableView alloc] initWithFrame:self.view.bounds style:UITableViewStylePlain];        _tableView.dataSource =self;        _tableView.delegate =self;        [_tableView registerClass:[ShopInfoCell class] forCellReuseIdentifier:identifier];        _tableView.rowHeight = 80;    }    return _tableView;}- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {        return self.dataList.count;}- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {        ShopInfoCell * cell = [tableView dequeueReusableCellWithIdentifier:identifier];        cell.shop = self.dataList[indexPath.row];        return cell;}- (void)viewDidLoad {    [super viewDidLoad];    // Do any additional setup after loading the view, typically from a nib.        [self.view addSubview:self.tableView];        //使用MJRefresh给我们的talbleView添加下拉刷新上拉加载控件        self.tableView.mj_header = [MJRefreshNormalHeader headerWithRefreshingTarget:self refreshingAction:@selector(loadNewData)];        self.tableView.mj_footer = [MJRefreshBackNormalFooter footerWithRefreshingTarget:self refreshingAction:@selector(loadMoreData)];        //    [self loadNewData];        //进入界面执行下拉刷新方法    [self.tableView.mj_header beginRefreshing];        }//上拉加载更多- (void)loadMoreData {            NSString * urlString = [NSString stringWithFormat:@"%@%@",SERVER_HOST,API_GetRestaurantsList];            NSDictionary * params = @{@"full_image_path":@"1",                              @"geohash":@"wx4u14w0649y",                              @"limit":@(shopInfoPageLimit),                              @"offset":@(self.page * shopInfoPageLimit),                              @"type":@"geohash",                              @"extras[]":@"food_activity",                              @"extras[]":@"restaurant_activity"};            [[HttpClient defaultClient] requestWithPath:urlString method:HttpRequestGet paramenters:params prepareExecute:^{                [ToolHelper showProgressMessage:@"我在刷新"];            } success:^(NSURLSessionDataTask *task, id responseObject) {        NSLog(@"%@",responseObject);                //JSON -> MODEL 有很多框架，原理都是KVC.                //MJExtenstion  JsonModel  Mantle  YYModel                //请求的分页数据 +1                //当返回到数据的count值为0时，说明已经全部加载完毕。                        NSArray * shopList = [Shop mj_objectArrayWithKeyValuesArray:responseObject];                //        if (shopList.count == 0) {        //        //            //显示已经全部加载完毕        //            [self.tableView.mj_footer endRefreshingWithNoMoreData];        //        }                if (self.page > 2) {                        [self.tableView.mj_footer endRefreshingWithNoMoreData];                    } else  {                        [self.dataList addObjectsFromArray:shopList];                        [self.tableView reloadData];                        //将上拉加载控件弹下去            [self.tableView.mj_footer endRefreshing];                        self.page ++ ;        }                                [ToolHelper showSuccessMessage:@"请求成功"];            } failure:^(NSURLSessionDataTask *task, NSError *error) {        NSLog(@"%@",error);                //将上拉加载控件弹下去        [self.tableView.mj_footer endRefreshing];                [ToolHelper showErrorMessage:@"请求失败"];    }];}//下拉刷新- (void)loadNewData {            NSString * urlString = [NSString stringWithFormat:@"%@%@",SERVER_HOST,API_GetRestaurantsList];        //下拉刷新，上拉加载  请求的地址是一样的 ，只是参数不一样的。    //limit 是不变的、改变 offset。。    //        //下拉刷新是加载最新数据，将page页数至为0.    //上拉加载加载更多数据。将page++        //MJRefresh  EGO下拉刷新  UIRefreshCotrol 自已写上拉下拉        NSDictionary * params = @{@"full_image_path":@"1",                              @"geohash":@"wx4u14w0649y",                              @"limit":@(shopInfoPageLimit),                              @"offset":@(0),                              @"type":@"geohash",                              @"extras[]":@"food_activity",                              @"extras[]":@"restaurant_activity"};            [[HttpClient defaultClient] requestWithPath:urlString method:HttpRequestGet paramenters:params prepareExecute:^{                [ToolHelper showProgressMessage:@"我在刷新"];            } success:^(NSURLSessionDataTask *task, id responseObject) {        NSLog(@"%@",responseObject);                //JSON -> MODEL 有很多框架，原理都是KVC.                //MJExtenstion  JsonModel  Mantle  YYModel                //请求的分页数据 +1                self.page = 1 ;                //获取最新数据前删除之前的所有数据        [self.dataList removeAllObjects];                NSArray * shopList = [Shop mj_objectArrayWithKeyValuesArray:responseObject];                [self.dataList addObjectsFromArray:shopList];                [self.tableView reloadData];                //重置没有更多的数据（消除没有更多数据的状态）        [self.tableView.mj_footer resetNoMoreData];                //将下拉刷新控件弹上去        [self.tableView.mj_header endRefreshing];                [ToolHelper showSuccessMessage:@"请求成功"];            } failure:^(NSURLSessionDataTask *task, NSError *error) {        NSLog(@"%@",error);                //将下拉刷新控件弹上去        [self.tableView.mj_header endRefreshing];        [ToolHelper showErrorMessage:@"请求失败"];    }];}- (void)didReceiveMemoryWarning {    [super didReceiveMemoryWarning];    // Dispose of any resources that can be recreated.}@end
     

大家是不是觉得少了些什么，当然是cell的自定义了，蛮简单了。看看就好。

ShopIconCell.h ShopIconCell.m

////  ShopIconCell.h//  CX－小项目（饿了么 网络部分 简单实现）////  Created by ma c on 16/3/23.//  Copyright © 2016年 xubaoaichiyu. All rights reserved.//#import 
     
      #import 
      
       #import "Shop.h"@interface ShopInfoCell : UITableViewCell@property (nonatomic, strong) Shop * shop;@end
      
     

////  ShopIconCell.m//  CX－小项目（饿了么 网络部分 简单实现）////  Created by ma c on 16/3/23.//  Copyright © 2016年 xubaoaichiyu. All rights reserved.//#import "ShopIconCell.h"#import "UIImageView+WebCache.h"static CGFloat kMargin = 5;@interface ShopInfoCell ()@property (nonatomic, strong) UIImageView * iconView;@property (nonatomic, strong) UILabel * nameLabel;@property (nonatomic, strong) UILabel * descLabel;@end@implementation ShopInfoCell-  (void)setShop:(Shop *)shop {        _shop = shop;            [self.iconView sd_setImageWithURL:[NSURL URLWithString:shop.image_path] placeholderImage:nil];        self.nameLabel.text = shop.name;    self.descLabel.text = shop.desc;}- (UIImageView *)iconView {        if (!_iconView) {        _iconView = [[UIImageView alloc] init];    }    return _iconView;}- (UILabel *)nameLabel {        if (!_nameLabel) {        _nameLabel = [[UILabel alloc] init];    }    return _nameLabel;}- (UILabel *)descLabel {        if (!_descLabel) {        _descLabel = [[UILabel alloc] init];    }    return _descLabel;}-(instancetype)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString *)reuseIdentifier {        if (self = [super initWithStyle:style reuseIdentifier:reuseIdentifier]) {                [self.contentView addSubview:self.iconView];        [self.contentView addSubview:self.nameLabel];        [self.contentView addSubview:self.descLabel];            }    return self;}- (void)layoutSubviews {        [super layoutSubviews];        self.iconView.frame = CGRectMake(kMargin, kMargin, 70, 70);        self.nameLabel.frame = CGRectMake(CGRectGetMaxX(self.iconView.frame) + kMargin, CGRectGetMinY(self.iconView.frame), SCREEN_WIDTH - CGRectGetMaxX(self.iconView.frame) - 2 * kMargin, 20);        self.descLabel.frame = CGRectMake(CGRectGetMinX(self.nameLabel.frame), CGRectGetMaxY(self.nameLabel.frame) + kMargin, CGRectGetWidth(self.nameLabel.frame), 20);        }- (void)awakeFromNib {}- (void)setSelected:(BOOL)selected animated:(BOOL)animated {    [super setSelected:selected animated:animated];    }@end

就这样一个小项目就这么的完成了。