Object reference not set to an instance of an Object C#

I forgot to mention I have a Generator and then a button the button is the child of the Generator and the GeneratorCastTrigger is attached to the ButtonObject

 

I don't understand what any of that means without more context.

In the Unity Inspector, Do the gameobjects that GeneratorObject/11/3 reference have a GeneratorCastTrigger/1/2 component attached to them? It can not be on a parent or child of that gameobject.

EDIT: It sounds like you have attached the components to a child gameobject. GetComponent will not get any components attached to child gameobjects, for that, you want GetComponentInChildren.

Code (CSharp):

1.         generatorcasttrigger = GeneratorObject.GetComponentInChildren<GeneratorCastTrigger>();
2.         generatorcasttrigger1 = GeneratorObjectll.GetComponentInChildren<GeneratorCastTrigger1>();
3.         generatorcasttrigger2 = GeneratorObject3.GetComponentInChildren<GeneratorCastTrigger2>();

 

Oh thanks

Edit: I don't think it worked

and what I meant is that the script is a child of the Door_Script gameobject and the generatorObject

 

The VariableObject gameobject has the Door_Script and the ButtonObject has the GeneratorCastTrigger

 

Show the inspector for VariableObject

 

Here you go

 

Are you sure that your ButtonObject1 has a "GeneratorCastTrigger2" component, and that your "ButtonObject2" has a "GeneratorCastTrigger1", and that your ButtonObject3 has a "GeneratorCastTrigger"?

Make sure you have attached the correct script to the correct object. It's looks confusing enough that it would be easy to make a mistake like this (why would a variable called "GeneratorObject3" reference an object called "ButtonObject1" which has a script called "GeneratorCastTrigger2" on it?)

 

Yes I've triple checked

Edit: oh oops made a mistake

Edit: Thank you it worked it stressed me out so much!

 

and now the game crashes when I try to interact with the button

 

so how do I make it so I can interact with the 3 scripts (acts as a Button) so I can activate all 3 of them

 

Provide the editor log (https://docs.unity3d.com/Manual/LogFiles.html) to help fix crashes.

This is not really relevant to this thread anymore. You may want to consider posting your new question in a new thread.

 

okay thanks for the help
but what thread tho?

 

also it's showing the same message now too "Object reference not set to an instance of an object 51"
on my interaction script tho

 

Have you tried to debug this yourself? e.g. adding debug statements to see what is null.

 

Yes But im gonna try this again

 

here's the script all three GetComponent isn't working

 

the interaction Script isn't working

 

So...

What did you discover when you tried debugging the script? e.g. did any of the debug statements get hit? What was the exact error?

You need to provide more information if you want help with something.

 

"NullRefrenceException: Object refrence not set to an instance of an object interact.update() (at Asset/ScriptingFile/interact.cs:20)"

 

That tells you that whatever your ray hit, it's parent doesn't have a "GeneratorCastTrigger" attached.

Your next step should be checking to see specifically what object your ray is hitting, and verifying that it's parent has the script you are trying to access.

 

How do I do that?

 

Code (CSharp):

1. using System.Collections;
2. using UnityEngine;
3.  
4. public class Interact : MonoBehaviour
5. {
6.     public float interactDistance = 5f;
7.  
8.     void Update()
9.     {
10.      if (Input.GetKeyDown(KeyCode.E))
11.         {
12.             Ray ray = new Ray(transform.position, transform.forward);
13.          
14.             RaycastHit hit;
15.  
16.             if (Physics.Raycast (ray, out hit, interactDistance))
17.             {
18.                 if (hit.collider.CompareTag("Generator"))
19.                 {
20.                     hit.collider.transform.parent.GetComponent<GeneratorCastTrigger>().Restate();
21.                     Debug.Log("Hit.Collider 1 is working");
22.  
23.                     hit.collider.transform.parent.GetComponent<GeneratorCastTrigger2>().Restate();
24.                     Debug.Log("Hit.Collider 2 is working");
25.  
26.                     hit.collider.transform.parent.GetComponent<GeneratorCastTrigger1>().Restate();
27.                     Debug.Log("Hit.Collider 3 is working");
28.                 }
29.             }
30.              
31.         }
32.     }
33. }
34.  

do I add a GetComponenetInChildren

 

Did you try?

Try adding GetComponenetInChildren and seeing what happens.

To find the name of the object the ray is hitting, put it a debug statement:

Code (CSharp):

1. Debug.Log(hit.collider.transform)

Check that that objects parent has the script you are trying to get.

 

It doesn't say anything... just says

"NullRefrenceException: Object refrence not set to an instance of an object interact.update() (at Asset/ScriptingFile/interact.cs:20)"

 

Where did you put the debug statement? Your posts tend to lack useful details.

You need to put debug statements everywhere and print everything to find out what is going on. Don't wait for me to tell you where to put them.

 

Code (CSharp):

1. public class Interact : MonoBehaviour
2. {
3.     public float interactDistance = 5f;
4.  
5.     void Update()
6.     {
7.      if (Input.GetKeyDown(KeyCode.E))
8.         {
9.             Ray ray = new Ray(transform.position, transform.forward);
10.            
11.             RaycastHit hit;
12.  
13.             if (Physics.Raycast (ray, out hit, interactDistance))
14.             {
15.                 if (hit.collider.CompareTag("Generator"))
16.                 {
17.                     hit.collider.transform.parent.GetComponentInChildren<GeneratorCastTrigger>().Restate();
18.                     Debug.Log(hit.collider.transform);
19.  
20.                     hit.collider.transform.parent.GetComponentInChildren<GeneratorCastTrigger2>().Restate();
21.                     Debug.Log(hit.collider.transform);
22.  
23.                     hit.collider.transform.parent.GetComponentInChildren<GeneratorCastTrigger1>().Restate();
24.                     Debug.Log(hit.collider.transform);
25.                 }
26.             }
27.                
28.         }
29.     }
30. }
31.  
32. there you go

 

How is trying to print the exact same colliders transform 3 times going to be useful in any way?

Read through your code. First, it detects if you pressed the E key (add a debug statement to verify this works), then it performs a raycast (debug statement to verify that it hit something), then it compares the objects tag (another debug log statement to check what the tag is of the hit object), then it tries to get the GeneratorCastTrigger component of the transforms parent (assign this to a variable, then add another debug statement to verify that it is actually sucessfully getting a script), then it calls Restate() etc etc

As part of the normal debugging process, your code should end up looking something like this:

Code (CSharp):

1. public class Interact : MonoBehaviour
2. {
3.     public float interactDistance = 5f;
4.     void Update()
5.     {
6.      if (Input.GetKeyDown(KeyCode.E))
7.         {
8.             Debug.Log("Pressed E");
9.             Ray ray = new Ray(transform.position, transform.forward);
10.        
11.             RaycastHit hit;
12.             if (Physics.Raycast (ray, out hit, interactDistance))
13.             {
14.                 Debug.Log("Hit object with tag " + hit.collider.gameObject.tag);
15.                 if (hit.collider.CompareTag("Generator"))
16.                 {
17.                     Debug.Log("parent " + hit.collider.transform.parent);
18.                     var generator1 = hit.collider.transform.parent.GetComponentInChildren<GeneratorCastTrigger>();
19.                     Debug.Log("generator1 " + generator1 );
20.                     generator1 .Restate();
21.                     // etc
22.                  
23.                 }
24.             }
25.            
26.         }
27.     }
28. }
29.  

 

Same error message

 

Of course you get the same error message. The point of the above example isn't to fix the bug (it's functionally identical), it's to output useful information to help you track down the bug.

 

also heres an image

The script is in the ButtonObject Component

I also changed the script

Code (CSharp):

1.  void Update()
2.     {
3.         if (Input.GetKeyDown(KeyCode.E))
4.         {
5.             Debug.Log("Pressed E");
6.             Ray ray = new Ray(transform.position, transform.forward);
7.  
8.             RaycastHit hit;
9.             if (Physics.Raycast(ray, out hit, interactDistance))
10.             {
11.                 if (hit.collider.CompareTag("Generator"))
12.                 {
13.                     hit.collider.transform.parent.GetComponentInChildren<GeneratorCastTrigger>().Restate();
14.                 }
15.                 if (hit.collider.CompareTag("Generator1"))
16.                 {
17.                     hit.collider.transform.parent.GetComponentInChildren<GeneratorCastTrigger1>().ReInitiate();
18.                 }
19.                 if (hit.collider.CompareTag("Generator2"))
20.                 {
21.                     hit.collider.transform.parent.GetComponentInChildren<GeneratorCastTrigger2>().Recreate();
22.                 }
23.             }
24.         }
25.     }
26.  

 

Use Debug.Log to check what object your ray is hitting, and verify that the children of that objects parent has the GeneratorCastTrigger/1/2 script attached somewhere.

 

Turns out the "GetComponentInChildren" Command messes the game up and crashes the game Thank you and sorry to bother you

 

i got the same problem pls help me here is the script i very new so i need more help

using System;
using System.Collections;
using System.Collections.Generic;
using System.Numerics;
using UnityEngine;

public class Movement : MonoBehaviour
{
public float movesp = 10f;
[SerializeField] private bool isgrounded = false;
private Animator animator;


// Start is called before the first frame update
void Start()
{
animator.GetComponent<Animator>();
}

private void OnTriggerEnter2D(Collider2D other)
{
if (other.CompareTag("ground"))
isgrounded = true;
}
private void OnTriggerExit2D(Collider2D other)
{
if (other.CompareTag("ground"))
isgrounded = false;
}
// Update is called once per frame

void Update()
{
float m = Input.GetAxis("Horizontal");
UnityEngine.Vector3 movement = new UnityEngine.Vector3(m, 0, 0);
transform.position = transform.position + movement * movesp * Time.deltaTime;

if (Input.GetButtonDown("Jump") && isgrounded == true)
{
GetComponent<Rigidbody2D>().AddForce(new UnityEngine.Vector3(0f, 7.5f), ForceMode2D.Impulse);


}
if (m != 0)
{
animator.SetFloat("speed", 1);
}
if (m==0)
{
animator.SetFloat("speed", 0);
}
}


}

 

you're missing alot of "{}"
Example

Code (CSharp):

1. if (other.CompareTag("ground"))
2. {
3. isgrounded = false
4. }

 

I am having a similar problem. When I kill and respawn my character the joystick control is disappearing after my character is destroyed.
.

 

The fact that it is bold in the first image tells me that it is a change that has not been applied to the player prefab.

Apply the change so that the prefab has a reference to the joystick. If you cannot do this (e.g. because your FixedJoystick component exists in the scene and not on the player prefab), then consider another way of fetching a reference to the joystick. For example, you could do something like:

mj = GameObject.FindObjectOfType<FixedJoystick>();

in the PlayerMovement's Start function.

 

Thank you very much

 

Hi! I am New to Unity and the I have a problem with my script

Here is the script:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class PlayerController : MonoBehaviour {

public float speed;
public float jumpForce;
public float moveInput;

private Rigidbody2D rb;

void start(){
rb = GetComponent<Rigidbody2D>();
}

void FixedUpdate(){

moveInput = Input.GetAxis("Horizontal");
rb.velocity = new Vector2(moveInput * speed, rb.velocity.y);
}

}


And here is the error message:

NullReferenceException: Object reference not set to an instance of an object
PlayerController.FixedUpdate () (at Assets/PlayerController.cs:20)

 

Please don't reply to old posts. It's actually explicitly against forum rules.

Instead, start your own post.

For null reference errors, this is literally THE MOST COMMON and THE SIMPLEST ERROR ever.

The answer is always the same... ALWAYS. It is the single most common error ever.

Don't waste your life spinning around and round on this error. Instead, learn how to fix it fast... it's EASY!!

Some notes on how to fix a NullReferenceException error in Unity3D
- also known as: Unassigned Reference Exception
- also known as: Missing Reference Exception
- also known as: Object reference not set to an instance of an object

http://plbm.com/?p=221

The basic steps outlined above are:
- Identify what is null
- Identify why it is null
- Fix that.

Expect to see this error a LOT. It's easily the most common thing to do when working. Learn how to fix it rapidly. It's easy. See the above link for more tips.

This is the kind of mindset and thinking process you need to bring to this problem:

https://forum.unity.com/threads/why-do-my-music-ignore-the-sliders.993849/#post-6453695

Step by step, break it down, find the problem.

 

thank you LMAOOO

 

Hey Guys!, i could really use your help, i'm having a problem with my script. Here it is:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;

public class CounterController : MonoBehaviour
{
int numberOfBoxes;
Text counterView;

// Start is called before the first frame update
void Start()
{
ResetCounter();
}

public void IncrementCounter()
{
numberOfBoxes++;
counterView.text = numberOfBoxes.ToString();
}

public void ResetCounter()
{
numberOfBoxes = 0;
counterView.text = numberOfBoxes.ToString();
}
}

And this is my error message

NullReferenceException: Object reference not set to an instance of an object
CounterController.ResetCounter () (at Assets/CounterController.cs:26)
CounterController.Start () (at Assets/CounterController.cs:14)

 

Please stop replying to posts from 2014 for a simple null reference. Null ref does NOT require a post even.

Why?

The answer is always the same... ALWAYS. It is the single most common error ever.

Don't waste your life spinning around and round on this error. Instead, learn how to fix it fast... it's EASY!!

Some notes on how to fix a NullReferenceException error in Unity3D
- also known as: Unassigned Reference Exception
- also known as: Missing Reference Exception
- also known as: Object reference not set to an instance of an object

http://plbm.com/?p=221

The basic steps outlined above are:
- Identify what is null
- Identify why it is null
- Fix that.

Expect to see this error a LOT. It's easily the most common thing to do when working. Learn how to fix it rapidly. It's easy. See the above link for more tips.

This is the kind of mindset and thinking process you need to bring to this problem:

https://forum.unity.com/threads/why-do-my-music-ignore-the-sliders.993849/#post-6453695

Step by step, break it down, find the problem.

Here is a clean analogy of the actual underlying problem of a null reference exception:

https://forum.unity.com/threads/nul...n-instance-of-an-object.1108865/#post-7137032

 

Closing.
Debugging is critical to any kind of software development. These errors have the line number right in them.
This thread is several years old and has all the solutions needed for this issue. (Including the post above this one). Read them, follow them. Null refs are a common user error you to learn to solve, not post on the internets looking for help.