nsurlconnection - NSURLConnection 的 didReceiveData 方法中 appendData 的奇怪问题

Question

我在植入简单的 NSURLConnection 时遇到了这个奇怪的问题...

调用了 didReceiveData 方法，我很乐意尝试附加接收数据，但是... nada!

肯定有一些数据(如长度所示，但 appendData 不附加数据!

我开始思考这个问题，我需要一些帮助，以免为时已晚:-)

这里有一些代码要看:

我的标题...

@interface ActionViewController : UITableViewController {
 Site *site;

 NSURLConnection *siteConnection;
 NSMutableData *receivedData;
    UIView *waitView;
    UIActivityIndicatorView *activityIndicator;

 int nConnections;
    BOOL fail;
}

我的实现..

- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
    // Append the new data to receivedData.
 NSLog(@"Received %d bytes of data",[data length]);
    [receivedData appendData:data];
 NSLog(@"Received %d bytes of data",[receivedData length]);
}

- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{

    NSLog(@"Succeeded! Received %d bytes of data",[receivedData length]);

 [UIApplication sharedApplication].networkActivityIndicatorVisible = NO;
 [activityIndicator stopAnimating];
 waitView.hidden = YES;

    // release the connection
    [connection release];
}

控制台输出...

[Session started at 2010-08-21 21:27:55 -0400.]
2010-08-21 21:28:19.263 myApp[2042:207] Received 108 bytes of data
2010-08-21 21:28:19.263 myApp[2042:207] Received 0 bytes of data
2010-08-21 21:28:19.263 myApp[2042:207] Succeeded! Received 0 bytes of data

我不明白!帮助!!!

顺便说一句，数据是一个简单的 xml 结果，看起来像这样......

<donnee>0</donnee><donnee>0</donnee><donnee>0</donnee><donnee>1</donnee><donnee>0</donnee><donnee>0</donnee>

Answer 1

好吧，我在这个网站上关于 NSMutableData 的另一个问题中得到了答案。 ...忘记初始化了! (代码 18 或向 nil 发送消息的剩余部分是 Objective-C 的一个 NICE 特性)

receivedData = [[NSMutableData alloc] init];