多NSURLCoonections使用iPhone SDK的

Question

可以在任何一个你发布的代码片段，例如教您如何使用可可触摸框架从相同的viewController处理多个

NSURLConnections ....

感谢所有你未来的帮助.....

Answer 1

看到这个链接的答案。它用asihttp包装nsurlconnection，这会让你的生活变得更容易。

Does ASIHTTP support multi threads?

Answer 2

我经手使用的NSMutableDictionary其跟踪哪些NSMutableData实例的特定NSURLConnection的应该保存它的结果多NSUrlConnections。

在我上课的时候，我定义：

NSMutableDictionary *dataDictionary; 

我loadData方法

然后，我有：

 // Create the request 
    NSURLRequest *theRequest=[NSURLRequest requestWithURL:[NSURL URLWithString:currentCam] 
               cachePolicy:NSURLRequestReloadIgnoringLocalCacheData 
              timeoutInterval:30]; 

    // create the connection with the request 
    // and start loading the data 
    NSURLConnection *theConnection=[[NSURLConnection alloc] initWithRequest:theRequest delegate:self]; 
    if (theConnection) { 

     NSMutableData *receivedData = receivedData = [[NSMutableData alloc] init]; 

     //keep track of this connection by adding it to subViewDictionary and dataDictionary with appropriate objects. 
     [dataDictionary setObject:receivedData forKey:[theConnection description]]; 
    } 

    else { 

     NSLog(@"ERROR DOWNLOADING WITH NSURLCONNECTION"); 
    } 

    [theConnection release]; 

我用[theConnection说明】如我的钥匙和MSMutableData的一个实例作为我的字典中的对象，所以稍后我可以查找哪个实例与特定连接一起使用。如果你不这样做，你可能会遇到数据损坏的问题（多个连接都可以将他们的数据保存到同一个变量中）。

然后，我定义如下NSURLConnection的委托方法：

- (void)connection:(NSURLConnection *)connection didReceiveData:(NSMutableData *)data 
{ 
    //look up in dictionary to find out which recievedData instance to use. 
    NSMutableData *theReceivedData = [dataDictionary objectForKey:[connection description]]; 

    // Append the new data to receivedData. 
    [theReceivedData appendData:data]; 
} 


- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response 
{ 
     //Lookup in the dictionary to find the correct instance of recievedData to put image into. 
    NSMutableData *theReceivedData = [dataDictionary objectForKey:[connection description]]; 
    [theReceivedData setLength:0]; 
    [activityIndicator stopAnimating]; 
} 

- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error 
{ 
    // inform the user that there was an error 
    NSLog(@"Connection failed! Error - localizedDescription:%@ NSURLErrorFailingURLStringErrorKey:%@", 
      [error localizedDescription], 
      [[error userInfo] objectForKey:NSURLErrorFailingURLStringErrorKey]); 


    NSMutableData *theReceivedData = [dataDictionary objectForKey:[connection description]]; 
    [theReceivedData release]; 

    //remove keys for this connection since it did not load. 
    [dataDictionary removeObjectForKey:[connection description]]; 
} 

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

    //look up correct instance of recievedData in teh dictionary for this connection 
    NSMutableData *theReceivedData = [dataDictionary objectForKey:[connection description]]; 

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

    //---do stuff with data here// 

    [theReceivedData release]; 
} 

有上NSURLConnection的here一个很好的教程为一个单独的连接。我的代码是基于此，增加了NSMutableDictionary来跟踪每个NSUrlConnection和每个NSMutableData实例。

我希望这是有道理的，是有帮助的！