NullReferenceException in Unity3d using unityscript

Question

I have this script below and at the lines 61 and 70, I get the error below for each line.

NullReferenceException: Object reference not set to an instance of an object
GameObject.Find("FPSArms_Axe@Idle").GetComponent(PlayerController).enabled = true;
GameObject.Find("FPSArms_Axe@Idle").GetComponent(PlayerController).enabled = false;

Code:

#pragma strict

var menuSkin : GUISkin;

var wood : int = 0;
var stone : int = 0;
var clay : int = 0;

var fish : int = 0;
var cookedFish : int = 0;

var bottle : int = 0;
var bottledWater : int = 0;

var bandage : int = 0;

var minimumVal : int = 0;

private var showGUI : boolean = false;

private var playerGUI : PlayerGUI;

function Start() {
    playerGUI = GameObject.Find("First Person Controller").GetComponent(PlayerGUI);
}

function Update() {
    if(wood <= 0) {
        wood = minimumVal;
    }
    if(stone <= 0) {
        stone = minimumVal;
    }
    if(clay <= 0) {
        clay = minimumVal;
    }
    if(fish <= 0) {
        fish = minimumVal;
    }
    if(cookedFish <= 0) {
        cookedFish = minimumVal;
    }
    if(bottle <= 0) {
        bottle = minimumVal;
    }
    if(bottledWater <= 0) {
        bottledWater = minimumVal;
    }
    if(bandage <= 0) {
        bandage = minimumVal;
    }
    if(Input.GetKeyDown("i")) {
        showGUI = !showGUI;
    }

    if(showGUI == true) {
        Time.timeScale = 0;
        GameObject.Find("First Person Controller").GetComponent(FPSInputController).enabled = false;
        GameObject.Find("First Person Controller").GetComponent(MouseLook).enabled = false;
        GameObject.Find("Main Camera").GetComponent(MouseLook).enabled = false;
        GameObject.Find("FPSArms_Axe@Idle").GetComponent(PlayerController).enabled = false;
        GameObject.Find("Main Camera").GetComponent(RayCastCollect).enabled = false;
    }

    if(showGUI == false) {
        Time.timeScale = 1;
        GameObject.Find("First Person Controller").GetComponent(FPSInputController).enabled = true;
        GameObject.Find("First Person Controller").GetComponent(MouseLook).enabled = true;
        GameObject.Find("Main Camera").GetComponent(MouseLook).enabled = true;
        GameObject.Find("FPSArms_Axe@Idle").GetComponent(PlayerController).enabled = true;
        GameObject.Find("Main Camera").GetComponent(RayCastCollect).enabled = true;
    }
}

function OnGUI() {
    if(showGUI == true) {
        GUI.skin = menuSkin;
            GUI.BeginGroup(new Rect(Screen.width / 2 - 150, Screen.height / 2 - 150, 300, 300));
                GUI.Box(Rect(0, 0, 300, 300), "Inventory");

                //Resources collected
                GUI.Label(Rect(10, 50, 50, 50), "Wood");
                GUI.Box(Rect(60, 50, 20, 20), "" + wood);

                GUI.Label(Rect(90, 50, 50, 50), "Stone");
                GUI.Box(Rect(130, 50, 20, 20), "" + stone);

                GUI.Label(Rect(170, 50, 50, 50), "Clay");
                GUI.Box(Rect(200, 50, 20, 20), "" + clay);


                //Empty holders
                GUI.Label(Rect(10, 130, 50, 50), "Fish");
                GUI.Box(Rect(60, 130, 20, 20), "" + fish);

                GUI.Label(Rect(10, 150, 50, 50), "Bottle");
                GUI.Box(Rect(60, 150, 20, 20), "" + bottle);

                //Edible items
                GUI.Label(Rect(10, 190, 50, 50), "CFish");
                GUI.Box(Rect(60, 190, 20, 20), "" + cookedFish);
                if(GUI.Button(Rect(100, 190, 100, 20), "Eat Fish?")) {
                    if(cookedFish >= 1) {
                        cookedFish--;
                        Eat();
                    }
                }

                GUI.Label(Rect(10, 210, 50, 50), "BWater");
                GUI.Box(Rect(60, 210, 20, 20), "" + bottledWater);
                if(GUI.Button(Rect(100, 210, 100, 20), "Drink Water?")) {
                    if(bottledWater >= 1) {
                        bottledWater--;
                        Drink();
                    }
                }

                GUI.Label(Rect(10, 240, 50, 50), "Heal");
                GUI.Box(Rect(60, 240, 20, 20), "" + bandage);
                if(GUI.Button(Rect(100, 240, 100, 20), "Use Bandage?")) {
                    if(bandage >= 1) {
                        bandage--;
                        Heal();
                    }
                }
                GUI.EndGroup();
    }
}

function Eat() {
    playerGUI.hungerBarDisplay += 0.1;
}

function Drink() {
    playerGUI.thirstBarDisplay += 0.1;
}

function Heal() {
    playerGUI.healthBarDisplay += 0.1;
}

Hard to tell without knowing your gameobjects, but my first guess would be, that there is either no GameObject that matches or the GameObject is inactive or it does not contain a PlayerController — Markai, Nov 18 '14 at 14:42
possible duplicate of [What is a NullReferenceException and how do I fix it?](http://stackoverflow.com/questions/4660142/what-is-a-nullreferenceexception-and-how-do-i-fix-it) — CodeSmile, Nov 18 '14 at 15:36

score 0 · Accepted Answer · answered Nov 18 '14 at 15:32

if your gameobject is deactivated it wont be found
it is better to use the generic method of get component GetComponent.<PlayerController>()
.if the PlayerController is in the parent of FPSArms_Axe@Idle it wont be found with GetComponent(PlayerController)
if PlayerController is in children of FPSArms_Axe@Idle you should use GetComponentInChildren
the only case that this will work is PlayerController is attached to FPSArms_Axe@Idle

NullReferenceException in Unity3d using unityscript

1 Answers1