Question

我正在创建一个显示我的Twitter时间线的应用。但我有时会收到以下错误：

Error Domain=NSCocoaErrorDomain Code=3840 "The operation couldn’t be completed. (Cocoa error 3840.)" (JSON text did not start with array or object and option to allow fragments not set.) UserInfo=0x1fd807c0 {NSDebugDescription=JSON text did not start with array or object and option to allow fragments not set.}

我使用以下代码检索twitter的时间轴：

-(void) getTimeLine{

ACAccountStore *account=[[ACAccountStore alloc] init];
ACAccountType *accountType=[account accountTypeWithAccountTypeIdentifier:ACAccountTypeIdentifierTwitter];
[activityIndicatorLoadTweets setHidden:NO];
[activityIndicatorLoadTweets startAnimating];
[account requestAccessToAccountsWithType:accountType options:nil completion:^(BOOL granted, NSError *error)
{
    if (granted==YES) {
        NSArray *arrOfAccounts=[account accountsWithAccountType:accountType];
        if ([arrOfAccounts count]!=0)
        {
            ACAccount *twitterAccount=[arrOfAccounts lastObject];
            NSURL *requestURL=[NSURL URLWithString:@"http://api.twitter.com/1/statuses/home_timeline.json"];
            NSMutableDictionary *params=[[NSMutableDictionary alloc] init];
            [params setObject:@"20" forKey:@"count"];
            [params setObject:@"1" forKey:@"include_entities"];

            SLRequest *postRequest=[SLRequest requestForServiceType:SLServiceTypeTwitter requestMethod:SLRequestMethodGET URL:requestURL parameters:params];

            postRequest.account=twitterAccount;

            [postRequest performRequestWithHandler:^(NSData *responseData, NSHTTPURLResponse *urlResponse, NSError *error)
            {
                if (responseData==nil) {
                    NSLog(@"Could not connect. Try Again.");
                    [self showLabelAndStartTimer];
                    lblStatus.text=@"Could not connect at the moment. Please try Again.";
                    [activityIndicatorLoadTweets setHidden:YES];
                    [activityIndicatorLoadTweets stopAnimating];
                }
                else{
                    lblStatus.hidden=YES;
                    self.arrDataSource=[NSJSONSerialization JSONObjectWithData:responseData options:NSJSONReadingMutableLeaves error:&error];

                    if ([self.arrDataSource count]!=0)
                    {
                        dispatch_async(dispatch_get_main_queue(), ^
                        {
                            [self.tableTweetsView reloadData];
                            [activityIndicatorLoadTweets setHidden:YES];
                            [activityIndicatorLoadTweets stopAnimating];
                            //[self fetchBollyTweetsFrom:self.arrDataSource];
                        });
                    }
                }

            }];

        }
    }
    else{
        NSLog(@"Failure to access acount. Please check your internet connection.");
        [activityIndicatorLoadTweets setHidden:YES];
        [activityIndicatorLoadTweets stopAnimating];
    }


}];

}

请注意，错误说明来自以下行：

self.arrDataSource=[NSJSONSerialization JSONObjectWithData:responseData options:NSJSONReadingMutableLeaves error:&error];

错误主要是自我解释但如果我的JSON错误，为什么我在一半时间内获得成功回复？对于代码的评论和建议也很受欢迎，因为我是iOS编程和使用JSON的新手。感谢。

Answer 1

与api.twitter.com的连接仅限于TLS / SSL连接。如果您的应用程序仍使用HTTP纯文本连接，则需要更新它以使用HTTPS连接点击此链接：https://dev.twitter.com/discussions/24239

Answer 2

添加以下代码以获取完整的JSON字符串，并了解错误背后的原因：

NSString* newStr = [[NSString alloc] initWithData:responseData 
                                         encoding:NSUTF8StringEncoding];
NSLog(@"%@", newStr);
self.arrDataSource=[NSJSONSerialization JSONObjectWithData:responseData options:NSJSONReadingMutableLeaves error:&error];

希望它有所帮助。

Answer 3

您的代码正在调用Twitter API的版本1 officially retired on June 11, 2013。您应该使用v1.1。

iOS - Twitter连接问题：“操作无法完成。（Cocoa error 3840.）”

3 个答案: