具有NSOperation的异步NSURLConnection [英] Asynchronous NSURLConnection with NSOperation

问题描述

我想在后台模式下执行 NSURLConnection ，因为它的响应有很多数据。论坛要求使用Apple的有限长度编码在 didEnterBackground 。
但是我想避免它。而不是它我使用以下代码通过 NSOperation 与 NSInvocation 一样，但它没有用。 connectToServer 有 NSURLConnection operation.any help please？ didReceiveData ， didReceiveResponse 不调用委托方法？

I want to do NSURLConnection in background mode,because it response is having much data.Forums are telling to use Apple's finite length coding to use in didEnterBackground. but I want to avoid it.instead of it I use following code through NSOperation with NSInvocation as, but it is not working.connectToServer is having NSURLConnection operation.any help please?didReceiveData,didReceiveResponse delegate methods are not called?

 NSOperationQueue *queue = [NSOperationQueue new];

NSInvocationOperation *operation = [[NSInvocationOperation alloc] initWithTarget:self
                                                                        selector:@selector(connectToServer)
                                                                          object:nil];

[queue addOperation:operation];
[operation release];
[queue autorelease];

 -(void)connectToServer
{
NSURL *url = [NSURL URLWithString:@"http://www.google.com"];
NSMutableURLRequest *theRequest = [NSMutableURLRequest requestWithURL:url];
NSURLConnection *theConnection = [[[NSURLConnection alloc] initWithRequest:theRequest delegate:self] autorelease];

    if( theConnection )
    {
        webData = [[NSMutableData data] retain];
    }
    else
    {
        NSLog(@"theConnection is NULL");
    }
}

推荐答案

这有点问题被问了很多时间。代理人没有被调用，因为从iOS 4开始，操作是在辅助线程上启动的。线程可能会在代理被调用之前退出。

This kind of question was asked a zillion time. Delegates are not getting called because as of iOS 4 operations are started on a secondary thread. The thread probably exits before the delegates are called that's all.

保持主线程上的连接并使用GCD处理后台线程中的数据。

Keep the connection on the main thread and handle the data in a background thread using GCD.

我在这里写了所有这些内容： http://cocoaintheshell.com/2011/04/nsurlconnection-synchronous-asynchronous/

I'v wrote about all this stuff here : http://cocoaintheshell.com/2011/04/nsurlconnection-synchronous-asynchronous/

编辑：更新链接。

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