Text in Canvas is not being updated correctly - Null Error

Question

I am building out a Zelda game and I have ran into an issue -

 public void UpdateCoins()
{
   Debug.Log(GameManager.instance.currCoins);
   //coinsText.text = "Coins " + GameManager.instance.currCoins;
}

That works as expected -

But when I do this...

  public void UpdateCoins()
{
   Debug.Log(GameManager.instance.currCoins);
   coinsText.text = "Coins " + GameManager.instance.currCoins;
}

I receive an Object Reference not set to an instance of the object error.

As you can see it is set. Here is my simple GameManager script

public static GameManager instance;

public int currCoins;

private void Awake()
{
    instance = this;
}
// Start is called before the first frame update
void Start()
{
    
}

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


public void GetCoins(int coinsToAdd)
{
    currCoins += coinsToAdd;

    UIManager.instance.UpdateCoins();
}
}

Any thoughts on why this isn't working the way it should?

Thanks!

Can you please [edit] the post to clarify what "TMP not being set correctly" means? — Alexei Levenkov, Dec 29 '22 at 21:38
Does this answer your question? [What is a NullReferenceException, and how do I fix it?](https://stackoverflow.com/questions/4660142/what-is-a-nullreferenceexception-and-how-do-i-fix-it) — , Dec 29 '22 at 22:10

score 1 · Answer 1 · answered Dec 29 '22 at 21:33

1

Try add more logs Either the coinsText or the coinsText.text is null, so what I would do is:

Debug.Log(coinsText);
if(coinsText != null) Debug.Log(coinsText.text);

answered Dec 29 '22 at 21:33

Jan Skála

374
4
13

That is super weird - Debug.Log(coinsText) sends a null value - It is set in the inspector. So it shouldn't be Null. – Wattsjmichael Dec 29 '22 at 22:01
@Wattsjmichael this is why you shouldn’t use **static**. Apart from your singletons that serve no purpose, you obviously have a stale and/or orphaned reference. – Dec 29 '22 at 22:17

score 0 · Answer 2 · answered Dec 30 '22 at 09:39

I'm sure you'll make a great Zelda game but let's fix your issue here first , you are trying to access to an int GameManager.instance.currCoins but returns null simply because the currCoins you're using is not even to been set to zero. Also as a tip if you are going to use an int in a string text or something always use ToString() : coinsText.text = "Coins " + GameManager.instance.currCoins.ToString(); Number 2 issue here , your use of singleton it should be like this

public static GameManager instance;

public void Awake()
{
    if(instance == null){
        instace = this;
    }else
    {
        DontDestroyOnLoad(gameObject);
    }
}

Last issue that may not be one now but in the future change the name of this method now while you still can public void GetCoins(int coinsToAdd)to something like AddCoins(int coinsToAdd)

Text in Canvas is not being updated correctly - Null Error

2 Answers2