Why does this give a "nullReferenceException"?

Question

 class some : MonoBehaviour
 {
 
     public some()
     {
         Invoke("wait", 2.0f);
     }
 
    void wait()
     {
 
     }
 
 }

Just making an instance of this class gives me a "nullReferenceException" for some reason.. same happens when trying to call a corouritine from this class.

And before someone suggests not inheriting from MonoBehaviour, i can't because i really want to have a delay and unity has made that impossible without a MonoBehaviour.

Answer 1

Answer by hexagonius · Nov 07, 2018 at 10:03 PM

you must not use a constructor for MonoBehaviour derived classes at all. those solely exist on gameobjects, either in the scene or on prefabs. For the latter use Instatiate to make one.

Add comment · Share

Answer 2

Answer by Matt1000 · Nov 07, 2018 at 10:51 PM

As they said, you shouldn't use constructors in component classes. If you need to call a method as soon as the object is created (either when you instantiate a new object or the scene is loaded with it) you should do it in Start or in Awake. Those to are automatically called. If you want a non-component class then just remove the inheritance from Monobehaviour.

Add comment · Share

Why does this give a "nullReferenceException"?

2 Replies

Your answer

Welcome to Unity Answers

Follow this Question

Related Questions