Null Reference Exception Error | Official Unity Discord | Page 1

queen citrus Mar 14, 2024, 6:13 PM

#

Hey, guys! Can you help me please with Null Reference that I am dealing with? So, I am making a flappy bird game and whenever my player enters the collider of the other object(gem) it disappears and my particle is being instantiated with object pooling method. So, what's happening basically is that instead of returning my gem particle game object back to its pool for one reason I am destroying it or something but as I see on my code I don't have any Destroy() method or something that destroys the object I have replaced everything. Check what is happening in the video below.

#

PlayerController.cs

📎 message.txt

#

ObjectPooling.cs

#

using UnityEngine;

public class ObjectPooling : MonoBehaviour
{
    public static ObjectPooling Instance;

    [Header("POOLING FIELDS")]
    public GameObject objectPrefab;
    [SerializeField] private int poolSize = 50;
    [SerializeField] private bool autoGrow = false;
    [SerializeField] private List<GameObject> objectPoolingList = new List<GameObject>();

    private void Awake()
    {
        for (int i = 0; i < poolSize; i++)
        {
            CreateObject();
        }
    }

    private GameObject CreateObject()
    {
        GameObject obj = Instantiate(objectPrefab, Vector3.zero, Quaternion.identity);
        objectPoolingList.Add(obj);
        obj.SetActive(false);
        return obj;
    }

    public GameObject GetPooledObject()
    {
        GameObject pooledObject = null;
        foreach (GameObject obj in objectPoolingList)
        {
            if (obj != null && !obj.activeInHierarchy)
            {
                pooledObject = obj;
                break;
            }
        }
        if (pooledObject == null)
        {
            if (autoGrow)
            {     
                pooledObject = CreateObject();
            }
            else
            {
                Debug.LogWarning("Unable to create object but it is required");
            }
        }
        return pooledObject;
    }
}```

#

light breach Mar 14, 2024, 6:17 PM

#

queen citrus

you didn't answer Digi's question

#

are these particles?

queen citrus Mar 14, 2024, 6:17 PM

#

Yeah join the thread I will

light breach Mar 14, 2024, 6:18 PM

#

they probably are set to Destroy

queen citrus Mar 14, 2024, 6:18 PM

#

Tell digit to join the thread we are going to discuss it here

#

#

Check it out

#

It is a particle that I am spawning

light breach Mar 14, 2024, 6:25 PM

#

queen citrus It is a particle that I am spawning

show that is not set to destroy

queen citrus Mar 14, 2024, 6:25 PM

#

How?

#

In my code I dont have anything that destroys it

#

I am pretty sure of that

light breach Mar 14, 2024, 6:25 PM

#

Is that it Stop Action

#

i forgot

queen citrus Mar 14, 2024, 6:25 PM

#

except if I lose something like a script

queen citrus Mar 14, 2024, 6:25 PM

#

light breach Is that it Stop Action

I didn't catch you here?

#

Wdym?

dreamy hollow Mar 14, 2024, 6:26 PM

#

Put a script on that object that logs something in OnDestroy, then check the stack trace to see what calls destroy

light breach Mar 14, 2024, 6:27 PM

#

queen citrus I didn't catch you here?

Yeah nvm what I said then, stop action is set to none..

queen citrus Mar 14, 2024, 6:27 PM

#

So, you think that's why it's happening?

light breach Mar 14, 2024, 6:28 PM

#

no, it would've been Destroy but its not.
Did you try what digi said, put log inside the object

queen citrus Mar 14, 2024, 6:28 PM

#

Let me check for a min documentation about that

queen citrus Mar 14, 2024, 6:28 PM

#

light breach no, it would've been Destroy but its not. Did you try what digi said, put log i...

You mean the tree log?

#

Or debug.log

#

If you meant the tree log I just did it the problem is with my gem particle

#

My tree logs are fine and collision is fine

light breach Mar 14, 2024, 6:30 PM

#

queen citrus If you meant the tree log I just did it the problem is with my gem particle

so put a script on Gem object

#

I never mentioned anything about trees

queen citrus Mar 14, 2024, 6:31 PM

#

No sorry

#

Collision and gem particles are not fine

#

they are not returned

#

only the logs

light breach Mar 14, 2024, 6:31 PM

#

on the particle object you put a script ?

#

yu only need 1 method

queen citrus Mar 14, 2024, 6:32 PM

#

How to call the script

#

Like a new class to make

light breach Mar 14, 2024, 6:32 PM

#

Test

queen citrus Mar 14, 2024, 6:32 PM

#

Ok

#

And put it inside my particle prefab?

light breach Mar 14, 2024, 6:32 PM

#

void OnDestroy()
{
  Debug.Log(name + " Was Destroyed");
}

#

then check where the call comes from

light breach Mar 14, 2024, 6:33 PM

#

queen citrus And put it inside my particle prefab?

it goes on GemParticleEffect object

#

the prefab yes

queen citrus Mar 14, 2024, 6:35 PM

#

Yeah I done that you said

#

It says that the gem particle is destroyed

light breach Mar 14, 2024, 6:36 PM

#

queen citrus It says that the gem particle is destroyed

wa

#

it print the log, select the log and screenshot

#

it shows the full strack trace

queen citrus Mar 14, 2024, 6:37 PM

#

#

Here what it says for my collision particle as well

#

#

Here is the gem particle log

light breach Mar 14, 2024, 6:39 PM

#

hmm thats strange..

queen citrus Mar 14, 2024, 6:39 PM

#

So, how can I continue tracing the issue?

#

There is no information

#

Maybe thats the issue because I am getting that warning

#

#

It says that the referenced script is missing

#

I am not sure what it means

#

what's missing actually?

light breach Mar 14, 2024, 6:42 PM

#

maybe you saved something / script during playmode?

queen citrus Mar 14, 2024, 6:43 PM

#

Inspect my scripts whenever you have time guys I am going to try and find whats happening. Don't know yet how to trace the issue. I am going to show you the line that error occurs the null reference.

light breach Mar 14, 2024, 6:44 PM

#

queen citrus Inspect my scripts whenever you have time guys I am going to try and find whats ...

do you know how to search all scripts?

queen citrus Mar 14, 2024, 6:45 PM

#

There is a command?

#

PlayerController.cs
https://paste.mod.gg/adveuowdfmjr/0

BlazeBin - adveuowdfmjr

A tool for sharing your source code with the world!

#

ObjectPooling.cs
https://paste.mod.gg/nmgdvxlpeoqf/1

BlazeBin - nmgdvxlpeoqf

A tool for sharing your source code with the world!

light breach Mar 14, 2024, 6:46 PM

#

#

ctrl + F

queen citrus Mar 14, 2024, 6:46 PM

#

#

What I am going to write here?

#

It says was not found Destroy

light breach Mar 14, 2024, 6:48 PM

#

queen citrus

first of all doesnt match anything I shown

#

first you have to set it to Current project /

#

then you need FIND ALL

queen citrus Mar 14, 2024, 6:51 PM

#

Yeah I have only OnDestroy method that I wrote before

#

SpawnManager.cs
https://paste.mod.gg/btetwjxqyhvh/2

BlazeBin - btetwjxqyhvh

A tool for sharing your source code with the world!

light breach Mar 14, 2024, 6:57 PM

#

did you write Destroy in search or OnDestroy

queen citrus Mar 14, 2024, 7:48 PM

#

I wrote Destroy

#

Also, I just find out where is the source of the issue

#

So, actually it is in ObjectPooling.cs

#

Unable to create object but it is required UnityEngine.Debug:LogWarning (object) ObjectPooling:GetPooledObject () (at Assets/Scripts/GameScene/ObjectPooling.cs:50) PlayerController:OnTriggerEnter2D (UnityEngine.Collider2D) (at Assets/Scripts/GameScene/PlayerController.cs:69)

#

Thats what it says

#

The issue persists first of all in ObjectPooling.cs and after that at the PlayerController.cs where I am calling it.

#

using UnityEngine;

public class ObjectPooling : MonoBehaviour
{
    public static ObjectPooling Instance;

    [Header("POOLING FIELDS")]
    public GameObject objectPrefab;
    [SerializeField] private int poolSize = 50;
    [SerializeField] private bool autoGrow = false;
    [SerializeField] private List<GameObject> objectPoolingList = new List<GameObject>();

    private void Awake()
    {
        Instance = this;
        for (int i = 0; i < poolSize; i++)
        {
            CreateObject();
        }
    }

    private GameObject CreateObject()
    {
        GameObject obj = Instantiate(objectPrefab, Vector3.zero, Quaternion.identity);
        objectPoolingList.Add(obj);
        obj.SetActive(false);
        return obj;
    }

    public GameObject GetPooledObject()
    {
        GameObject pooledObject = null;
        foreach (GameObject obj in objectPoolingList)
        {
            if (obj != null && !obj.activeInHierarchy)
            {
                pooledObject = obj;
                break;
            }
        }
 
        if (pooledObject == null)
        {
            if (autoGrow)
            {     
                pooledObject = CreateObject();
            }
            else
            {
                Debug.LogWarning("Unable to create object but it is required");
            }
        }
        return pooledObject;
    }
}```

#

Check the GetPooledObject()

#

Something happening there with the if statements

#

The pooled object is null because we give it this value so it is true and then it enters the inside if statement which is false. It never goes true

queen citrus Mar 15, 2024, 6:46 PM

#

@light breach Hey! Are you available to help me?

light breach Mar 15, 2024, 7:06 PM

#

queen citrus <@968604165150507078> Hey! Are you available to help me?

Im at work so not much but whats the problem ?

queen citrus Mar 15, 2024, 7:15 PM

#

Nothing when you get back we will discuss it whenever you will have time.

#

Don't worry do you job 🙂

#

I am not in hurry

queen citrus Mar 17, 2024, 5:40 PM

#

@light breach Hello! Are you available for 20 minutes to help me with my issue?

light breach Mar 17, 2024, 5:42 PM

#

sure but only this time, post on code channel next time,.I'd rather not get @ with questions.

queen citrus Mar 17, 2024, 5:47 PM

#

Ok! So, where to start? What do you want to show you? I have my object pooling.cs and my player controller.cs. I found out where is the source of the issue. It is in ObjectPooling.cs and PlayerController.cs at the specific lines I am going to tell you.

light breach Mar 17, 2024, 5:54 PM

#

send both scripts then
https://hatebin.com

queen citrus Mar 17, 2024, 5:57 PM

#

ObjectPooling.cs
https://hatebin.com/qgosmdagpw

#

PlayerController.cs
https://hatebin.com/wfvpfhhozt

light breach Mar 17, 2024, 6:01 PM

#

do you have any scripts on gems ?

light breach Mar 17, 2024, 6:04 PM

#

queen citrus ObjectPooling.cs https://hatebin.com/qgosmdagpw

where did you get this pooling from ?

queen citrus Mar 17, 2024, 6:05 PM

#

I ve made that watch some tutorials got some help from chat gpt and tried to make that.

#

That was the first time I was making that I am not sure if I implement it correctly but I am not instantiating things as I did before

#

I am using somehow if not completely object pooling

#

For instantiating

light breach Mar 17, 2024, 6:06 PM

#

using GPT is not very good cause it makes nonsense code

queen citrus Mar 17, 2024, 6:06 PM

#

activating and deactivate things

#

That's trie

#

true

#

Sometimes it makes non sense

light breach Mar 17, 2024, 6:07 PM

#

I would lookup how the Unity one is

queen citrus Mar 17, 2024, 6:07 PM

#

But it helps for simple issues

#

Sometimes

light breach Mar 17, 2024, 6:07 PM

#

https://learn.unity.com/tutorial/introduction-to-object-pooling

#

issue is probably you're getting a poolobject to Active before returning the object first

queen citrus Mar 17, 2024, 6:09 PM

#

What is happening is that

#

inside my gem objecte pooling list when my player collects the gems I have pool size 10 it says missing game object till the final game object and then it starts to create again the game object and immediately set it back to missing game object

#

so it is something like

#

1-10 missing

#

I have

#

1-10 gem game objects and when I am collecting them

#

it says

light breach Mar 17, 2024, 6:11 PM

#

I would just remake the pooling

queen citrus Mar 17, 2024, 6:11 PM

#

missing for each till the 10

light breach Mar 17, 2024, 6:11 PM

#

and make it properly, actually learn how to use it

queen citrus Mar 17, 2024, 6:11 PM

#

I don't know yet how to implement it properly

light breach Mar 17, 2024, 6:11 PM

#

then you should not be using it

queen citrus Mar 17, 2024, 6:11 PM

#

I am not sure most of the code was from chat to tell you the truth

#

I wanted to make it because a guy told me to do that

light breach Mar 17, 2024, 6:11 PM

#

regardless, you should not have a system in the game unless you know how it works

queen citrus Mar 17, 2024, 6:12 PM

#

I was just instantiating and destroying game objects

#

rather thatn using object pool

light breach Mar 17, 2024, 6:12 PM

#

its good for performance yes, but now you trying to implement something you don't understand and it broke

queen citrus Mar 17, 2024, 6:12 PM

#

the guy told me to make that

#

Do I have to remove it now

#

I have two options

light breach Mar 17, 2024, 6:13 PM

#

You should leave it how you had it when it was working.. Then learn sepearely the proper way to pool untill you understand it

#

when you do that, you add the optimization

queen citrus Mar 17, 2024, 6:13 PM

#

Either I am removing it and making it like I had it before or you just help me remake that object pooling

#

I think I dont have other alternative

light breach Mar 17, 2024, 6:13 PM

#

I told you how to do it, put it like before since you understood what it was doing

#

then with time, even in a separate project..Play around with object pooling

queen citrus Mar 17, 2024, 6:14 PM

#

The guy told me what it does

light breach Mar 17, 2024, 6:14 PM

#

its dead simple now with the unity package they added

queen citrus Mar 17, 2024, 6:14 PM

#

I understood somehow

#

What it does

light breach Mar 17, 2024, 6:14 PM

#

not what it does you dont understsand how its working cause you wrote it overcomplicated than one unity provides

#

https://docs.unity3d.com/2021.1/Documentation/ScriptReference/Pool.ObjectPool_1.html

queen citrus Mar 17, 2024, 6:15 PM

#

Rather than instantiating and destroyign game objects it activates object from the pool whenever I want it to activate and deactivate it set these objects as inactive in hierarchy

light breach Mar 17, 2024, 6:15 PM

#

that theory behind is ok to know but is not enough

#

You have to understand HOW it does what it does

queen citrus Mar 17, 2024, 6:15 PM

#

I want to understand the whole syntax of this method

#

step by step

light breach Mar 17, 2024, 6:15 PM

#

I sent you 2 docs already

queen citrus Mar 17, 2024, 6:16 PM

#

Are there different variations?

light breach Mar 17, 2024, 6:16 PM

#

there are videos too, make sure they are the UNITY Pooling they added , not the custom ones

queen citrus Mar 17, 2024, 6:16 PM

#

Or only one that all of us implement when making object pool

light breach Mar 17, 2024, 6:16 PM

#

the one from UnityEngine.Pool

#

not a custom one

#

people make their own version, no need now. Unity has package

#

dead simple

#

its 3 methods

queen citrus Mar 17, 2024, 6:17 PM

#

It is in docs you send me?

#

The one of Unity?

#

with 3 methods?

light breach Mar 17, 2024, 6:17 PM

#

yes

Screen_Shot_2024-03-17_at_2.17.40_PM.png

#

well 4 methods but still..

#

https://unity.com/how-to/use-object-pooling-boost-performance-c-scripts-unity

queen citrus Mar 17, 2024, 6:22 PM

#

I will try to read these docs you send watch some tutorials and if you can send me some tutorials from people that use the unity original method of object pooling. I have to learn the methodology of how to implement it on my games.

light breach Mar 17, 2024, 6:25 PM

#

queen citrus I will try to read these docs you send watch some tutorials and if you can send ...

https://youtu.be/U08ScgT3RVM

YouTube

Unity

Level up your code with game programming design patterns: Object po...

In this video, you’ll learn more about object pooling, how it can provide performance optimization by reducing the processing power required of the CPU to run repetitive create and destroy calls, and how to use it in your Unity projects.

⭐ Learn more about programming design patterns in this e-book: https://on.unity.com/3O6tR8J
⭐ Check out Unit...

▶ Play video

queen citrus Mar 17, 2024, 6:28 PM

#

I have another question right now not related with that. I just enter Unity Learn with my account and I see zero progress. For one reason, I lost all of my progress do you know why this is happening because last time I remember I had so much exp and all of that?

#

I had a lot of tutorials saved there that I wanted to watch and courses and all of that

light breach Mar 17, 2024, 6:31 PM

#

I'm not sure , I haven't used the new website much

queen citrus Mar 17, 2024, 6:31 PM

#

I have heard that have happened to a lot of people

#

in reddit

light breach Mar 17, 2024, 6:31 PM

#

u sure its the correct account /email ?

queen citrus Mar 17, 2024, 6:32 PM

#

Yeah I had two accounts the one now I am in is my main

#

A guy says in reddit that there is a way to reset your account

#

But I am not sure how

#

Maybe I can contact unity

#

About that issue

#Null Reference Exception Error