One of my scripts has no check-box next to it in Inspector

Questions & Answers
1

I have created an empty gameobject and dragged four scripts onto it to control various things. One of them has no check-box next to it in the inspector and one of the others isn't being instantiated properly, meaning I'm getting an error:

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

I am referencing them like this:

public class DataLayer : MonoBehaviour {
private Configs configOb;
private PageLoader pl;

void Start() 
{
	configOb = (Configs)gameObject.GetComponent(typeof(Configs));
	//configOb = new Configs();
	//pl = new PageLoader();
	pl = (PageLoader)gameObject.GetComponent(typeof(PageLoader));
}

public ArrayList getTopApps() {
		ArrayList titleArray = new ArrayList();
		string fetchUrl = configOb.getRoot()+"TopTen.php";

When I test this code it fails at the bottom line because the configOb is null.

2

Your MonoBehaviour won't have a checkbox next to it in the inspector if it doesn't have any of the per-frame methods, like Update, FixedUpdate, OnGUI, etc.

I can't tell you why your configOb variable isn't being set properly. It may be due to something outside of the script you posted.

3

Is getTopApps() called by another script's Start() method? If so, it may be running before DataLayer.Start() is.

The convention I usually follow to avoid this is to put all reference assignment (GetComponent, Find, etc) in Awake, while startup functionality that relies on such references always goes in Start.