SDK的哪个版本有问题.所有的v3.x版本的SDK都提供了您提到的loginBehavior属性.在SDK的v4.0版本(3月25日发布)中，FBLoginView被FBSDKLoginButton取代，并且仍然提供了loginBehavior属性.

Which version of the SDK are you having problems with. All the v3.x versions of the SDKs provide that loginBehavior property like you mentioned. In v4.0 of the SDK (released March 25), the FBLoginView is replaced by FBSDKLoginButton and still offers a loginBehavior property.