Public class used in another class (C#)

Questions & Answers
1

Ok, i have a sort-of advanced problem, which i’m sure has a simple solution, but i just can’t manage to find it…

Let’s say i have a public class, designed to be editable from the inspector…

[System.Serializable]
public class PersonType {
    string gender;
    bool schoolEmployee;
    GameObject model;    
}

…and i use this class in another class, which i assign to a gameobject, where i set several instances of it (everything filled in inspector)…

public class PeopleTypes : MonoBehaviour {    
    public PersonData maleStudent;
    public PersonData femaleStudent;
    public PersonData Teacher;
    public PersonData Janitor;
}

…and i use the PersonType class as a part of another class (Person type defining the type of a person, Individual defining the individual parameters)…

public class Individual : MonoBehaviour {
    string name;
    int age;
    PersonType pType;    
}

…why do i get a nullreference exception when i try to set…

Individual ind_1 = new Individual();
ind_1.pType = PeopleTypes.maleStudent; //<- this is where i get the error

…or better yet, what would be the correct way of setting this? I guess a part of the problem would be whether this is the correct way to set up a public class for inspector editing…

2

You must not use new to instantiate MonoBehaviour classes.
Instead, you should instantiate components or game objects or don’t inherit from MonoBehaviour when you want to use “new”.

If you don’t need your class to have its own update, coroutine and the general Unity processing functionality, just use the classes you wrote without inheriting (or inheriting from non mono base class).

http://unity3d.com/support/documentation/ScriptReference/index.Instantiate.html