Access variable from a different scene in Unity

Question

I am fairly new to Unity and C# and am having some trouble. I am designing a 2d game, which has multiple levels. Each level contains a LevelManager which stores whether the leve

Answer 1

First, DontDestroyOnLoad is not supposed to do this - main usage for this is to implement things like unity-singleton (easy-to-use template). It means, you`ll have one instance of levelManager, not one per level.

To do it in your way, you need to load all the scenes additively, and get all the LevelManager instances. Or you can load all scenes one-by-one, getting level name and it`s isPassed value from current LevelManager. It can take a while, and its a wrong way.

The right way is to store inter-scene data in ScriptableObject models. It`s like a MonoBehaviour, but not related to scene - it just lays somewhere in project.

So, in your case, you can create ScriptableObject called LevelProgress. It will store the list of all passed levels. It will have public method LevelPassed(string levelName), as a parameter you can use anything - levels name, levels index in build, scene itself, whatever. Every time, when player passes any level, your LevelManager (remove DontDestoryOnLoad from it), which has a reference to LevelProgress scriptable object, will call LevelProgress.LevelPasses(currentLevel). And then, if you need to know, was some level passed, or not, you can just check, is LevelProgress.PassedLevels list contains this level.

Additionally, you need to implement between-sessions persistance for this scriptable object. IMO, the best way for this is to use JSONUtility to convert ScriptableObject into JSON string, and then write it to PlayerPrefs.