How do I present UIViewController from SKscene with social framework?

Question

I am making a game like Flappy Bird. How do I present a UIViewController from SKScene? First of all, I tell my environments

• Mac OS X 10.9
• Xcode 5.0.2

Answer 1

You cannot present a viewController from within a SKScene as it is actually only being rendered on a SKView. You need a way to send a message to the viewController, which in turn will present the viewController. For this, you can use delegation.

Add the following protocol definition to your SKScene's .h file:

@protocol sceneDelegate <NSObject>
-(void)showShareScreen;
@end

And declare a delegate property in the interface:

@property (weak, nonatomic) id <sceneDelegate> delegate;

Then, at the point where you want to present the share screen, instead of the line:

[self presentViewController:tweetSheet animated:YES completion:nil];

Use this line:

[self.delegate showShareScreen];

Now, in your viewController's .h file, implement the protocol:

@interface ViewController : UIViewController <sceneDelegate>

And, in your .m file, add the following line before you present the scene:

scene.delegate = self;

Then add the following method there:

-(void)presentShareScreen
{

    if ([SLComposeViewController isAvailableForServiceType:SLServiceTypeTwitter])
    {
        SLComposeViewController *tweetSheet = [SLComposeViewController
        composeViewControllerForServiceType:SLServiceTypeTwitter];
        [tweetSheet setInitialText:@"TestTweet from the Game !!"];
        [self presentViewController:tweetSheet animated:YES completion:nil];

    }
}

An alternate method would be to use NSNotificationCenter

Keep the -presentShareScreen method as described in the previous alternative.

Add the viewController as a listener to the notification in it's -viewDidLoad method:

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(presentShareScreen) name:@"showShareScreen" object:nil];

Then, in the scene at the point where you want to show this viewController, use this line:

[[NSNotificationCenter defaultCenter] postNotificationName:@"showShareScreen" object:nil];