How to run a function in a GO that have DontDestroyOnLoad

[Nivius_School]

The code i am using following

`using UnityEngine;
using System.Collections;

public class CollisonWin : MonoBehaviour
{

GameObject goMAINMENU;
public MainMenu MM;

void OnTriggerEnter(Collider collision)
{
    if (collision.gameObject.tag == "Player")
    {
		
		goMAINMENU = GameObject.Find("ScoreSystemCube");
		MM = goMAINMENU.gameObject.GetComponent();
		MM.SaveScore();

        Debug.Log("Winning!");

		Application.LoadLevel("2DKemi_Level2");
    }
}    

}`

SaveScore

using UnityEngine;
using System.Collections;

public class ScoreSystem : MonoBehaviour {
	public int score;
	public GUISkin Scoreskin;
	public bool saveScoreSetting;

	GameObject goMAINMENU;
	public MainMenu MM;

	public void ToggleScore()
	{

		goMAINMENU = GameObject.Find("ScoreSystemCube");
		MM = goMAINMENU.gameObject.GetComponent<MainMenu>();

		saveScoreSetting = MM.WhatModeIsIt();

		if (Application.loadedLevelName == "2DKemi_Level1")
		{
			
			
			if (saveScoreSetting == true)
			{
				//ADD points 
				score = 0;
			}
			if (saveScoreSetting == false)
			{
				//LOSE points
				score = 500;
			}
		}
		if (Application.loadedLevelName == "2DKemi_Level2")
		{
			if (saveScoreSetting == true)
			{
				//ADD points
				score = 0;
			}
			if (saveScoreSetting == false)
			{
				//LOSE points
				score = 1000;
			}

		}

	}


	public void AdjustScore(int adj)
	{
		if (saveScoreSetting == true)
		{
			if (adj < 0)//om minus poäng, sätt till 0;
			{
				adj = 0;
			}
		}
		if (saveScoreSetting == false)
		{
			if (adj > 0)//om plus poäng, sätt till 0;
			{
				adj = 0;
			}
		}

		if (score < 0)
		{
			score = 0;
		}
		else
		{
			score = score + adj;
		}
	}

	void OnGUI()
	{
		float InfoBoxWidth = (Screen.width * 0.15f);
		float InfoBoxheight = (Screen.height * 0.10f);
		float scoreBarLengthLock = (Screen.width / 4);


		GUI.skin = Scoreskin;


		GUI.Box(new Rect(Screen.width - (scoreBarLengthLock + 10), Screen.height - 32, (InfoBoxWidth*1.8f), InfoBoxheight), " ");
		GUI.Box(new Rect(Screen.width - (scoreBarLengthLock + 10), Screen.height - 32, (InfoBoxWidth*1.8f), InfoBoxheight), "Poäng: " + score);



		

	}

	void Start () {
		ToggleScore(); // CHANGES SCORE SYSTEM TO POSITIVE OR NEGATIVE
	}
	
	// Update is called once per frame
	void Update () {
		if (score < 0)
		{
			score = 0;
		}
	}
}

MainMenu

using UnityEngine;
using System.Collections;

public class MainMenu : MonoBehaviour {

	GameObject goPLAYER;

	public bool ChoosenMode;

	public int[] SavedScore = new int[10]; //totalpoäng i 0, poäng för bana 1 i 1, bana 2 i 2 osv.

	public GUISkin Scoreskin;
	public ScoreSystem SS;

	float InfoBoxwidth = (Screen.width * 0.15f);
	float InfoBoxheight = (Screen.height * 0.10f);

	float scoreBarLengthLock = (Screen.width / 4);
	
	void OnGUI()
	{
		if (Application.loadedLevelName == "Start_Menu")
		{
			GUI.skin = Scoreskin;
			if (GUI.Button(new Rect(((Screen.width / 2) - (InfoBoxwidth + 10)), ((Screen.height / 2) - (InfoBoxheight / 2)), InfoBoxwidth, InfoBoxheight), "+"))
			{
				ChoosenModeFunction(true);
				Application.LoadLevel("2DKemi_Level1");

			}
			if (GUI.Button(new Rect(((Screen.width / 2) + 10), ((Screen.height / 2) - (InfoBoxheight / 2)), InfoBoxwidth, InfoBoxheight), "-"))
			{
				ChoosenModeFunction(false);
				Application.LoadLevel("2DKemi_Level1");
			}

		}
	}


	void ChoosenModeFunction(bool Choosen_feedback)
	{
		ChoosenMode = Choosen_feedback;
		print("THE CHOSEN MODE IS: " + ChoosenMode);
	}

	public bool WhatModeIsIt()
	{
		return (ChoosenMode);
	}

	public void SaveScore()
	{
		int scoreToSave;
		scoreToSave = SS.score;
		if (Application.loadedLevelName == "2DKemi_Level1")
		{
			SavedScore[1] = scoreToSave;
			SavedScore[0] = SavedScore[0] + scoreToSave;
			print("PLAYER GOT THIS SCORE LAST MAP: " + scoreToSave);
		}

		if (Application.loadedLevelName == "2DKemi_Level2")
		{
			SavedScore[2] = scoreToSave;
			SavedScore[0] = SavedScore[0] + scoreToSave;
			print("PLAYER GOT THIS SCORE LAST MAP: " + scoreToSave);
		}
	}

	void awake()
	{

		//DontDestroyOnLoad(this);
        DontDestroyOnLoad(transform.gameObject);
		goPLAYER = GameObject.Find("First Person Controller");
		SS = goPLAYER.gameObject.GetComponent<ScoreSystem>();
		SS.ToggleScore();

		print("THE CHOSEN MODE IS: " + ChoosenMode);

	}
	
	void Start () {
	
	}
	
	// Update is called once per frame
	void Update () {
	
	}
}

This is seposed to findout when the player collide whit this objektive to make it a “goal” and then load the next map.

but before this i have had a simple script in the start that chooses if the game will use positive or negative feedback.
this is then stored in that GO.

in the same file i have a “save score” kind of function that saves the games score to an array

Error:
NullReferenceException: Object reference not set to an instance of an object
MainMenu.SaveScore () (at Assets/Standard Assets/Scripts/Scripts/MainMenu.cs:55)
CollisonWin.OnTriggerEnter (UnityEngine.Collider collision) (at Assets/Standard Assets/Scripts/Scripts/CollisonWin.cs:26)

as the go does not show up, but its still active, it reconnaissances it as null

PS: c# please

[Yokimato]

MM = goMAINMENU.gameObject.GetComponent();

From what you posted, your GetComponent call is missing the type parameters.

However, From your error message, your function SaveScore is throwing the exception, and there is a null reference somewhere in it. Since the code for that is not posted, this is as much help as one can give.

---

So now that we have the code, let’s find where the issue could be happening.

 public void SaveScore()
    {
       int scoreToSave;
       scoreToSave = SS.score; // <--- #1
       if (Application.loadedLevelName == "2DKemi_Level1")
       {
         SavedScore[1] = scoreToSave;
         SavedScore[0] = SavedScore[0] + scoreToSave; // #2
         print("PLAYER GOT THIS SCORE LAST MAP: " + scoreToSave);
       }
 
       if (Application.loadedLevelName == "2DKemi_Level2")
       {
         SavedScore[2] = scoreToSave;
         SavedScore[0] = SavedScore[0] + scoreToSave; // #3
         print("PLAYER GOT THIS SCORE LAST MAP: " + scoreToSave);
       }
    }

Above is 3 spots where you could be getting your error from. #1, if the variable SS is null. Otherwise, for 2 and 3, if SaveScore[0] is null, then concatenation on a null value would also trigger a NullReferenceException. Check these spots and you’ll find your answer