Question

我有一个从web服务加载一些数据的应用程序。一切都很好。

现在我想在后台进程中更新数据。写了这个部分，我可以通过在Xcode中使用“模拟背景提取”调试过程来启动它。
我的问题是AFHTTPRequestOperation中的块没有被执行。我打赌我不想在这里阻止，但是a）我想知道为什么它不会执行 - 我的猜测是你不能在背景提取中旋转这样的块。
b）我不知道怎么不在这里使用一块。

非常感谢任何帮助。

    - (void) callWebServiceUpdate {

    //Delete tmpDatabase if it is there
    NSFileManager *fileManager = [NSFileManager defaultManager];
    BOOL success;
    success = [fileManager fileExistsAtPath:self.tmpEmployeeDatabasePath];
    if (success) {
        [fileManager removeItemAtPath:self.tmpEmployeeDatabasePath error:nil];
    }

    //Write data to temp database
    AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];
    manager.requestSerializer = [AFJSONRequestSerializer serializer];
    [manager.requestSerializer setAuthorizationHeaderFieldWithUsername:@"USER" password:@"PASSWORD"];
    manager.responseSerializer = [AFJSONResponseSerializer serializer];

    AFHTTPRequestOperation *operationNow = [manager GET: @"https://xxxxxxxxx/mobile/mobilede.nsf/restServices.xsp/LotusDirectoryPeople"
                                          parameters: [self jsonDict]
                                             success: ^(AFHTTPRequestOperation *operation, id responseObject)

                                         {
                                             NSMutableArray  *employees = (NSMutableArray *)responseObject;
                                             FMDatabase *db = [FMDatabase databaseWithPath:self.tmpEmployeeDatabaseName];
                                             [db open];
                                             for(NSDictionary *dict in employees)
                                             {
                                                 BOOL success =   [db executeUpdate:@"INSERT INTO tmpemployees (id,firstName,lastName,fullName,email) VALUES (?,?,?,?,?);",
                                                                   [dict objectForKey:@"clockNumber"],
                                                                   [dict objectForKey:@"firstName"],
                                                                   [dict objectForKey:@"lastName"],
                                                                   [dict objectForKey:@"fullName"],
                                                                   [dict objectForKey:@"email"],
                                                                   nil];
                                                 if (success) {} // Only to remove success error
                                             }
                                         }

                                             failure:^(AFHTTPRequestOperation *operation, NSError *error)
                                         {NSLog(@"Error: %@", error);}
                                         ];
    [operationNow start];

    //Loop through the tmp db and see if we have a value to update or add
    //id tmpDatabasePath = [(AppDelegate *)[[UIApplication sharedApplication] delegate] databasePath];
    NSMutableArray *tmpEmployees;
    tmpEmployees = [[NSMutableArray alloc] init];

    FMDatabase *tmpDatabase = [FMDatabase databaseWithPath:self.tmpEmployeeDatabasePath];
    [tmpDatabase open];

    //id realDatabasePath = [(AppDelegate *)[[UIApplication sharedApplication] delegate] databasePath];
    FMDatabase *realDatabase = [FMDatabase databaseWithPath:self.employeeDatabasePath];
    [realDatabase open];


    FMResultSet *results = [tmpDatabase executeQuery:@"SELECT * FROM employees"];
    while([results next])
    {
        employee *thisEmployee      = [employee new];
        thisEmployee.firstName      = [results stringForColumn:@"firstName"];
        thisEmployee.lastName       = [results stringForColumn:@"lastName"];
        thisEmployee.fullName       = [results stringForColumn:@"fullname"];
        thisEmployee.city           = [results stringForColumn:@"city"];
        thisEmployee.ste            = [results stringForColumn:@"state"];
        thisEmployee.emailAddress   = [results stringForColumn:@"email"];

        NSString *tst = [results stringForColumn:@"id"];
        thisEmployee.id    = [NSNumber numberWithInt:[tst intValue]];

        //See if we have a record
        FMResultSet *results = [realDatabase executeQuery:@"SELECT * from db where id= ?",thisEmployee.id];




    }
    [tmpDatabase close];
}

======================================

下面的海报是正确的。我添加了这段代码：

NSURLSessionConfiguration *backgroundConfiguration = [NSURLSessionConfiguration backgroundSessionConfiguration:@"background"];
AFURLSessionManager *backgroundManager = [[AFURLSessionManager alloc] initWithSessionConfiguration:backgroundConfiguration];

但是，我不明白如何将我的JSON URL请求添加到AFURLSessionManager。

Answer 1

我不知道 AFNetworking 的内部结构，但需要使用 NSURLSession 和 NSURLSessionDownloadTask 对象完成后台提取。检查您调用的函数是否在内部使用适当的类 - 在正常操作中正常工作的方法可能只是拒绝在后台获取模式下工作。

在简要了解 AFNetworking 文档之后，我想您可能需要设置一个为背景提取配置的 AFURLSessionManager 实例。

Answer 2

彼得回答说，你需要使用NSURLSessions。 AFNetworking确实提供了会话管理器。请查看here。

对于后台任务，您需要使用后台配置创建NSURLSessionConfiguration。 Link to Apple Docs

AFURLSessionManager *manager = [[AFURLSessionManager alloc] initWithSessionConfiguration:[NSURLSessionConfiguration backgroundSessionConfiguration:@"com.yourapp.background.download"]];

iOS后台进程和AFNetworking

2 个答案: