NSURLConnectionDelegate

A protocol that delegates of a URL connection implement to receive status about and provide feedback to the connection object.

Declaration

protocol NSURLConnectionDelegate : NSObjectProtocol

Delegates of NSURLConnection objects should implement either the NSURLConnectionDataDelegate or NSURLConnectionDownloadDelegate protocol in addition to the NSURLConnectionDelegate protocol. Specifically:

If you are using NSURLConnection in conjunction with Newsstand Kit’s download(with:) method, the delegate class should implement the NSURLConnectionDownloadDelegate protocol.
Otherwise, the delegate class should implement the NSURLConnectionDataDelegate protocol.

Delegates that wish to perform custom authentication handling should implement the connection(_:willSendRequestFor:) method, which is the preferred mechanism for responding to authentication challenges. (See URLAuthenticationChallenge for more information on authentication challenges.) If connection(_:willSendRequestFor:) is not implemented, the older, deprecated methods connection(_:canAuthenticateAgainstProtectionSpace:), connection(_:didReceive:), and connection(_:didCancel:) are called instead.

The connection(_:didFailWithError:) method is called at most once if an error occurs during the loading of a resource. The connectionShouldUseCredentialStorage(_:) method is called once, just before the loading of a resource begins.