Swift Facebooklogin

我试图将下面的代码行从Objective C转换为新的编程语言Swift。 也许有人可以帮助我，并勾画出不同之处。 会很棒！

if (FBSession.activeSession.state == FBSessionStateCreatedTokenLoaded) { [FBSession openActiveSessionWithReadPermissions:@[@"public_profile"] allowLoginUI:NO completionHandler:^(FBSession *session, FBSessionState state, NSError *error) { // Handler for session state changes // This method will be called EACH time the session state changes, // also for intermediate states and NOT just when the session open [self sessionStateChanged:session state:state error:error]; }];} 

谢谢你，托比亚斯

Answer 1

这是我的答案：像FBSessionStateCreatedTokenLoaded几个关键字抛出错误，所以这可能有助于

 func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool { // Whenever a person opens the app, check for a cached session if FBSession.activeSession().state == FBSessionState.CreatedTokenLoaded { // If there's one, just open the session silently, without showing the user the login UI FBSession.openActiveSessionWithReadPermissions(["public_profile"], allowLoginUI: false, completionHandler: { (session, state, error) -> Void in self.sessionStateChanged(session, state: state, error: error) }) } return true } func sessionStateChanged(session : FBSession, state : FBSessionState, error : NSError?) { // If the session was opened successfully if state == FBSessionState.Open { println("Session Opened") } // If the session closed if state == FBSessionState.Closed { println("Closed") } } 

在button上单击做Facebooklogin

  @IBAction func FacebookLoginPressed(Sender: AnyObject) { if (FBSession.activeSession().state == FBSessionState.Open || FBSession.activeSession().state == FBSessionState.OpenTokenExtended) { // Close the session and remove the access token from the cache // The session state handler (in the app delegate) will be called automatically FBSession.activeSession().closeAndClearTokenInformation() } else { // Open a session showing the user the login UI // You must ALWAYS ask for public_profile permissions when opening a session FBSession.openActiveSessionWithReadPermissions(["public_profile"], allowLoginUI: true, completionHandler: { (session:FBSession!, state:FBSessionState, error:NSError!) in let appDelegate = UIApplication.sharedApplication().delegate as AppDelegate // Call the app delegate's sessionStateChanged:state:error method to handle session state changes appDelegate.sessionStateChanged(session, state: state, error: error) }) } } 

Answer 2

 func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: NSDictionary?) -> Bool { if FBSession.activeSession.state.value == FBSessionStateCreatedTokenLoaded.value { FBSession.openActiveSessionWithReadPermissions(self.facebookReadPermissions, allowLoginUI: true, completionHandler: {(session, state, error) -> Void in self.sessionStateChanged(session, state: state, error: error) }) } } func sessionStateChanged(session:FBSession, state:FBSessionState, error:NSError?) { } 

Answer 3

这是代码

 if FBSession.activeSession().state == FBSessionStateCreatedTokenLoaded { FBSession.openActiveSessionWithPublishPermissions("publish_actions", defaultAudience: FBSessionDefaultAudienceFriends, allowLoginUI: true, completionHandler: ^(session : FBSession, state : FBSessionState, error : NSError)) { // Handler for session state changes // This method will be called EACH time the session state changes, // also for intermediate states and NOT just when the session open self.sessionStateChanged(session, state: state, error: error) } } return true } func sessionStateChanged(session : FBSession, state : FBSessionState, error : NSError) { // If the session was opened successfully if state == FBSessionStateOpen { println("Session Opened") } } 

Answer 4

这可以简化为：

 let state = FBSession.activeSession().state if state == .Open && state == .OpenTokenExtended { FBSession.activeSession().closeAndClearTokenInformation() } else { FBSession.openActiveSessionWithReadPermissions(["public_profile"], allowLoginUI: true) { _ in FBSession.activeSession().closeAndClearTokenInformation() } }