如何使用FBLoginView检查Facebook登录？

Question

I am using FBLoginView to login to Facebook.

How do I check whether the user is logged in on the next launch?

I want the check to happen at the application level and not in a UIViewController like in the Facebook Tutorial on their Developers site.

If there is no way, then how can I add a Facebook Image which looks like a FBLoginView image to my custom button? Where can I find that image?

Answer 1

There are 2 delegate methods of FBLoginView

-(void)loginViewShowingLoggedOutUser:(FBLoginView *)loginView

-(void)loginViewShowingLoggedInUser:(FBLoginView *)loginView

The first method would inform you whether the user is logged out and the second method would inform you whether the user is logged in and you can perform your action on the basis of that.

For getting the image of the Profile picture u can use users id or objectID from this delegate method which contains all the user information.

-(void)loginViewFetchedUserInfo:(FBLoginView *)loginView user:(id<FBGraphUser>)user
{        
    NSURL *url = [NSURL URLWithString:[NSString stringWithFormat:@"https://graph.facebook.com/%@/picture?type=normal",user.id]];
    NSData  *data = [NSData dataWithContentsOfURL:url];
    UIImage *profileImage = [UIImage imageWithData:data];
}

where the profileImage would contain the user profile Image and you can use that image to show on your custom button.