can't acces a static variable from another script

Questions & Answers
1

the thing is i need a list of strings to be serialized and stored in the hard drive. To do that a followed the live training on persistent data, and tried to do the same. There are two scripts, one is GameManager

public class GameManager : MonoBehaviour
{
    public static GameManager manager;
    public string un;
    public List<string> names;

    void Start()
    {
        names.Add("Johny");
        names.Add("Nate");
        print(names);
    }
}

and the other script adds names to the names list in GameManager

public class AddNamee : MonoBehaviour {   
    void Start()
    {
        GameManager.manager.names.Add("Karim");
    }
}

when i run this i get the following error:
NullReferenceException: Object reference not set to an instance of an object
AddNamee.Start () (at Assets/AddNamee.cs:19)

2

I don’t see where the “manager” object was ever defined. You’re probably missing something like this in GameManager():

void Awake()
{
    if (manager == null)
    {
        manager = this;
    }
}