Ios 无法从完成处理程序进行网络调用？

我正在尝试访问用户表单电话的联系人。出于某种目的，我正在使用完成处理程序。因此，当应用程序尝试访问用户的联系人时，它会显示警报并请求允许联系人。当用户按下“确定”按钮时

然后执行一个块&此时我进行网络调用。虽然调用了函数，但从未调用委托&从未收到响应

ABAddressBookRef addressBookRef = ABAddressBookCreateWithOptions(NULL, NULL);
    if (ABAddressBookGetAuthorizationStatus() == kABAuthorizationStatusNotDetermined)
    {

        ABAddressBookRequestAccessWithCompletion(addressBookRef, ^(bool granted, CFErrorRef error) {
            // First time access has been granted, add the contact
            NSLog(@"access contact");
           [self sample];

        });
          NSLog(@"after sccess contact");

    }
    else if (ABAddressBookGetAuthorizationStatus() == kABAuthorizationStatusAuthorized)
    {
        // The user has previously given access, add the contact
        NSLog(@"previous access");
    }
    else
    {
        // The user has previously denied access
        // Send an alert telling user to change privacy setting in settings app
        NSLog(@"send alert");
    }
    CFErrorRef error = NULL;

网络呼叫

-(void)sample
{
    NSLog(@"sample func called");
    // Create the request.
    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:@"http://google.com"]];

    // Specify that it will be a POST request
    request.HTTPMethod = @"POST";

    // This is how we set header fields
    [request setValue:@"application/xml; charset=utf-8" forHTTPHeaderField:@"Content-Type"];

    // Convert your data and set your request's HTTPBody property
    NSString *stringData = @"some data";
    NSData *requestBodyData = [stringData dataUsingEncoding:NSUTF8StringEncoding];
    request.HTTPBody = requestBodyData;

    // Create url connection and fire request
    sampleConn= [[NSURLConnection alloc] initWithRequest:request delegate:self];
}

---

试试这个

替换您的代码

[self sample];

与

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您是否检查了failure delegate方法？是的，我已检查过。如果我使用[viewdidLoad]方法进行网络cal，则会收到响应。但在另一种情况下，我没有收到任何响应。@AshishP.Hey您之前的回答在我的演示代码中起作用。@AshishI认为您是在地址簿参考的完成块中进行ws调用，http请求还从完成块获取委托引用，即实际上是地址簿的委托引用。因此，finish方法不会在您的代理上被调用。

dispatch_async(dispatch_get_main_queue(), ^{

    [self sample];
});