如何使用 Facebook SDK 在我的应用程序中注销 Facebook

Question

我已经在我的应用程序中集成了 Facebook 登录，因此用户可以使用我的应用程序帐户和 Facebook 登录并执行相应的操作。对于 Facebook 集成，我添加了Facebook SDK 。现在当我的应用程序中单击注销按钮时，它必须清除所有Facebook 帐户的凭据。但是当我再次单击按钮时，我直接登录到我的帐户，而无需转到 Facebook 登录页面。

如何退出 Facebook？

- (void)viewDidLoad 
{
    [super viewDidLoad];

    // Do any additional setup after loading the view, typically from a nib.
    [self toggleHiddenState:YES];

    self.fbLoginStates.text = @"";
    self.loginButton.delegate = self;
    self.loginButton.readPermissions = @[@"public_profile", @"email"];
}

-(void)toggleHiddenState:(BOOL)shouldHide    
{
    self.lblUsername.hidden = shouldHide;
    self.lblEmail.hidden = shouldHide;
    self.profilePicture.hidden = shouldHide;
}

#pragma mark - FBLoginView Delegate method implementation

-(void)loginViewShowingLoggedInUser:(FBLoginView *)loginView
{        
    self.fbLoginStates.text = @"You are logged in.";

    [self toggleHiddenState:NO];
}

-(void)loginViewFetchedUserInfo:(FBLoginView *)loginView user:(id<FBGraphUser>)user
{        
    NSLog(@"%@", user);

    self.profilePicture.profileID = user.id;
    self.lblUsername.text = user.name;
    self.lblEmail.text = [user objectForKey:@"email"];
}

-(void)loginViewShowingLoggedOutUser:(FBLoginView *)loginView
{
    self.fbLoginStates.text = @"You are logged out";

    [self toggleHiddenState:YES];
}

-(void)loginView:(FBLoginView *)loginView handleError:(NSError *)error
{
    NSLog(@"%@", [error localizedDescription]);
}

Answer 1

在 AppDelegate .m

#import <FBSDKCoreKit/FBSDKCoreKit.h>
#import <FBSDKLoginKit/FBSDKLoginKit.h>

在 AppDelegate .m

return [[FBSDKApplicationDelegate sharedInstance] application:application
                                    didFinishLaunchingWithOptions:launchOptions];

在登录屏幕 .m:-

- (void)FacebookLogin:(id)sender {
//    [[NSNotificationCenter defaultCenter]addObserver:self selector:@selector(getFacebookData) name:@"getFacebookData" object:nil];
    FBSDKLoginManager *login = [[FBSDKLoginManager alloc] init];
    [login
     logInWithReadPermissions: @[@"public_profile", @"email", @"user_friends"]
     handler:^(FBSDKLoginManagerLoginResult *result, NSError *error) {
         if (error) {
             NSLog(@"Process error");
         } else if (result.isCancelled) {
             NSLog(@"Cancelled");
         } else {
             NSLog(@"Logged in");
             [MBProgressHUD showHUDAddedTo:self.view animated:YES];
              FBSDKGraphRequest *request = [[FBSDKGraphRequest alloc]
                                           initWithGraphPath:@"/me"
                                           parameters:@{ @"fields": @" email",}
                                           HTTPMethod:@"GET"];
             [request startWithCompletionHandler:^(FBSDKGraphRequestConnection *connection, id result, NSError *error) {
                 // Insert your code here
                 NSLog(@"%@",result);              
              [MBProgressHUD hideHUDForView:self.view animated:YES];
              } failedBlock:^{
              [MBProgressHUD hideHUDForView:self.view animated:YES];
                  UIAlertController * alert=   [UIAlertController alertControllerWithTitle:APP_NAME message:@"Could not connect to the server." preferredStyle:UIAlertControllerStyleAlert];
                  UIAlertAction* okButton = [UIAlertAction actionWithTitle:@"OK" style:UIAlertActionStyleDefault handler:^(UIAlertAction * action)
                                             {
                                                 //Handel your yes please button action here
                                                 [alert dismissViewControllerAnimated:YES completion:nil];

                                             }];
                  [alert addAction:okButton];
                  [self presentViewController:alert animated:YES completion:nil];
              }];

             }];

         }
     }];
}

在注销屏幕 .m 中：-

 -(IBAction)Logout:(id)sender
{
       [[FBSDKLoginManager new] logOut];    
}