How do I access a gameobject across classes

Questions & Answers
1

I am having some issues with Classes; still getting my head around OOP (pointers to good tutorials welcome - the one’s I’ve read weren’t so helpful).

Anyway, I’ve been trying to get this working for about an hour now - simply put - I want to access the gameobject in my script/class SnapToGrid.
This object is called from deploy_machine class which inherets from MonoBehaviour (if I understand that bit right)

public class deploy_machine : MonoBehaviour {

	private SnapToGrid snapper;

	void Awake () {
		snapper = new SnapToGrid(GameObject.Find(this.name));
	}
}

With my SnapToGrid looking like:

public class SnapToGrid {
	public GameObject game_object;
	public SnapToGrid(GameObject game_object){
		//Transform cached_transform
		SetupRigidbody();
		ConstructTrigger();
		game_object.renderer.material = green_material;
	}

	private void SetupRigidbody(){
		Rigidbody rb = game_object.rigidbody; //the rigidbody component of this object
	}
}

The problem is it fails inside SetupRigidbody (line 11 above).

NullReferenceException: Object reference not set to an instance of an object

So how do I structure/declare my new class to get access to the gameobject?
Thanks.

2

you didn’t save gameobject to your game_object variable in class constructor, i think.
try this constructor:

    public SnapToGrid(GameObject game_object){
       //Transform cached_transform
       this.game_object = game_object;
       SetupRigidbody();
       ConstructTrigger();
       game_object.renderer.material = green_material;
    }