AFNetworking 2.0 新特性讲解之AFHTTPSessionManager

来自：guandan521 > 《iOS开发》

AFNetworking 2.0 相比1.0 API 接口改动还是很大的. 其中一个便是 AFURLSessionManager,当然如果你不太熟悉,或者为了兼容低版本,你依然可以选择AFHTTPRequestOperationManager,AFURLSessionManager是基于

NSURLSessionConfiguration(IOS 7.0+, MAC OX10_9+)的.

下面我们借用TuneStore的API 来完成AFURLSessionManager的讲解.

如果您在看这边文章之前 我建议您首先阅读下AFNetworking2.0的官方新特性介绍.

AFNetworking 2.0
Migration Guide - 你如果之前用过AF1.0 这个是很有必要来看的.

AFNetworking 2.0 Docs

AFNetworking 2.0 Source

另外T*witer 上说NSHipster的AFNetworking现在翻译成中文了,所以我搬过来了有兴趣的朋友也可以去看下,https://github.com/NSHipster/articles/blob/zh-Hans/2013-09-16-afnetworking-2.md

1:创建 client search iTunes

#import "AFHTTPSessionManager.h"
@interface ITunesClient : AFHTTPSessionManager
+ (ITunesClient *)sharedClient;
- (NSURLSessionDataTask *)searchForTerm:(NSString *)term completion:( void (^)(NSArray *results, NSError *error) )completion;
@end

#import "ITunesClient.h"

@implementation ITunesClient

+ (ITunesClient *)sharedClient {
    static ITunesClient *_sharedClient = nil;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        NSURL *baseURL = [NSURL URLWithString:@"https://itunes.apple.com/"];

        NSURLSessionConfiguration *config = [NSURLSessionConfiguration defaultSessionConfiguration];
        [config setHTTPAdditionalHeaders:@{ @"User-Agent" : @"TuneStore iOS 1.0"}];
                //设置我们的缓存大小 其中内存缓存大小设置10M  磁盘缓存5M
        NSURLCache *cache = [[NSURLCache alloc] initWithMemoryCapacity:10 * 1024 * 1024
                                                          diskCapacity:50 * 1024 * 1024
                                                              diskPath:nil];
        
        [config setURLCache:cache];
        
        _sharedClient = [[ITunesClient alloc] initWithBaseURL:baseURL
                                         sessionConfiguration:config];
        _sharedClient.responseSerializer = [AFJSONResponseSerializer serializer];
    });
    
    return _sharedClient;
}

- (NSURLSessionDataTask *)searchForTerm:(NSString *)term completion:( void (^)(NSArray *results, NSError *error) )completion {
    NSURLSessionDataTask *task = [self GET:@"/search"                                  //为了速度我们将地区设置为台湾
                                parameters:@{ @"country" : @"TW",
                                              @"term" : term }
                                   success:^(NSURLSessionDataTask *task, id responseObject) {
                                       NSHTTPURLResponse *httpResponse = (NSHTTPURLResponse *)task.response;
                                       if (httpResponse.statusCode == 200) {
                                           dispatch_async(dispatch_get_main_queue(), ^{
                                               completion(responseObject[@"results"], nil);
                                           });
                                       } else {
                                           dispatch_async(dispatch_get_main_queue(), ^{
                                               completion(nil, nil);
                                           });
                                           NSLog(@"Received: %@", responseObject);
                                           NSLog(@"Received HTTP %d", httpResponse.statusCode);
                                       }
                                       
                                   } failure:^(NSURLSessionDataTask *task, NSError *error) {
                                       dispatch_async(dispatch_get_main_queue(), ^{
                                           completion(nil, error);
                                       });
                                   }];
    return task;
}
@end

Note:为了便于对这个任务进行(取消,监控等)操作 我们将这个任务返回.

2: 在view controller对client进行回调

NSURLSessionDataTask *task = [[ITunesClient sharedClient] searchForTerm:term
                                                                 completion:^(NSArray *results, NSError *error) {
                                                                     if (results) {
                                                                         self.results = results;
                                                                         [self.tableView reloadData];
                                                                     } else {
                                                                         NSLog(@"ERROR: %@", error);
                                                                     }
                                                                 }];

3: AFNetworking UIKit 之 加载网络图片

每一个cell 我们可以利用 AFNetworking对UIImageView的 category .只需要在文件中导入

#import
 "UIImageView+AFNetworking.h"

,然后

cellForRowAtIndexPath:

方法下直接使用即可

cell.artworkImageView.image = nil;
    [cell.artworkImageView cancelImageRequestOperation];

    NSURL *imageURL = [NSURL URLWithString:record[@"artworkUrl100"]];
    if (imageURL) {
        [cell.artworkImageView setImageWithURL:imageURL];
    }

4:当任务运行时显示 activity indicator

导入
 #import "UIActivityIndicatorView+AFNetworking.h"

[self.activityIndicator setAnimatingWithStateOfTask:task];

运行效果如下



demo 下载地址