Object reference; sometimes works but sometimes doesn't???

Questions & Answers
1

Hello Peeps, I’m no good at scripting so I could really do with some help.
I have 2 scripts that I am using, one works fine and the other doesn’t even though, as far as I’m aware, they are performing the same function.

The first script is a component of a box trigger that deactivates two other scripts that are on my player character and control his movement when the player enters that trigger. The player is then activated again on a button press:

public KeyCode Deactivate;

// Update is called once per frame
void Update () {
	if (Input.GetKeyDown (Deactivate)) {
		Cursor.lockState = CursorLockMode.Locked;
		gameObject.SetActive (false);
		GameObject.Find ("Player").GetComponent<CharacterMover> ().enabled = true;
		GameObject.Find ("Player").GetComponent<CharacterTurner> ().enabled = true;

	}
		
}

void OnTriggerEnter(Collider other) {

	Cursor.lockState = CursorLockMode.Confined;

	if (other.CompareTag ("Player")) {

		GameObject.Find("Player").GetComponent<CharacterMover>().enabled = false;
		GameObject.Find("Player").GetComponent<CharacterTurner>().enabled = false;
	}
}

}

That works fine, however another script that I want to activate a deactivated button on the same trigger scenario…:

void OnTriggerEnter(Collider other) {
	
	if (other.CompareTag ("Player")) {
		
		GameObject.Find ("Test Button 1").gameObject.SetActive (true);
	}
}

… gives me the following error:

NullReferenceException: Object reference not set to an instance of an object
ButtonActivation.OnTriggerEnter (UnityEngine.Collider other) (at Assets/ButtonActivation.cs:17)

I know line 17 is ‘GameObject.Find (“Test Button 1”).gameObject.SetActive (true);’ but I don’t understand why i get an error, any help would be very much appreciated thanks!

2

Avoid using GameObject.Find(“”), it causes performance issues, and only find ACTIVE objects, instead, use public variables that show in the inspector,

 GameObject.Find ("Test Button 1").gameObject.SetActive (true);

to:

 public GameObject testButton;

 void OnTriggerEnter(Collider other) {
     
     if (other.CompareTag ("Player")) {
         
         testButton.SetActive (true);
     }
 }
3

You absolute legend thanks for the help and the tips!!! I wonder why GameObject.Find causes performance issues? @AndreM1