Presenting a scene in SpriteKit without discarding the previous? - ios

Question

My situation is that I have a GameMenuScene and after the user chooses a level, I want to present the LevelScene. But I do not want to have the previous GameMenuScene discarded because the LevelScene is actually a #property of GameMenuScene and whether or not the user completes the level is to be saved as a #property of LevelScene, which the GameMenuScene should be able to access after the user finishes or exits the level. If I simply use presentScene:transition, the GameMenuScene is discarded and the information cannot pass back.
My question: Is there a way to stack or push the scenes on top of each other without discarding the previous (preferably using a transition animation)? I could not find a method for this specific purpose in the Apple Documentation for SKScene.
Note: Another StackOverflow answer to a similar question suggests to create a new UIViewController, present the LevelScene in there and then present the UIViewController modally. But I was hoping there was an existing method in the Apple Documentation that I have missed to present the scene itself scene modally without having to create UIVIewControllers.

Answer 1

There is no navigation controller-like capability for SKScenes that allows you to push and pop scenes. You will need to write code to manage and present your scenes.
Here's a simple view controller implementation that allows you to switch between two scenes (by swiping) without discarding the other scene.
#interface ViewController()
#property BOOL viewFlag;
#property SKScene *scene1;
#property SKScene *scene2;
#end
#implementation ViewController
- (void)viewDidLoad
{
[super viewDidLoad];
// Configure the view.
SKView * skView = (SKView *)self.view;
skView.showsFPS = YES;
skView.showsNodeCount = YES;
UISwipeGestureRecognizer *swipeGesture = [[UISwipeGestureRecognizer alloc]
initWithTarget:self action:#selector(handleSwipeGesture:)];
swipeGesture.direction = UISwipeGestureRecognizerDirectionRight;
[self.view addGestureRecognizer:swipeGesture];
// Create and configure scene 1.
SKScene * scene = [MyScene sceneWithSize:skView.bounds.size];
scene.scaleMode = SKSceneScaleModeAspectFill;
self.scene1 = scene;
// Present the scene 1.
[skView presentScene:scene];
// Create and configure scene 2.
scene = [MySecondScene sceneWithSize:skView.bounds.size];
scene.scaleMode = SKSceneScaleModeAspectFill;
self.scene2 = scene;
}
- (void) handleSwipeGesture:(id)sender
{
SKView * skView = (SKView *)self.view;
_viewFlag = !_viewFlag;
if (_viewFlag) {
[skView presentScene:_scene1];
}
else {
[skView presentScene:_scene2];
}
}
#end