Start function not calling?

I have this code;

Code (csharp):

1.  
2.     void Start(){
3.         Debug.Log ("add");
4.         if (isInventoryMain) {
5.             InventoryNumber = InventoryManager.GetComponent<InventoryManager> ().SlotManagerAdd (this.gameObject);
6.             Debug.Log ("added");
7.         }
8.     }
9.  

that calls another script's function. This is on every small cell and there is about 34 of them.
Theoretically, it should say "added', 34 times as all 34 have isInventoryMain ticked, but It doens't.
So I decided to add Debug.Log("add"); at the start and not even that gets called. I have the logs enabled in console so it is not that. so this means that the Start function is not calling at all?

This is the code in the other script if you are wondering;

Code (csharp):

1.  
2.     public int SlotManagerAdd (GameObject slot){
3.         InventorySlotsList.Add (slot);
4.         InventorySlots = InventorySlotsList.ToArray();
5.         Debug.Log ("Added slot");
6.         return InventorySlotsList.Count;
7.     }
8.  

It doesn't say "Added slot" either.

 

Is the script enabled, and on active gameobjects?
Also check your console. You can turn of Debug.Log messages in the upper right of the console window, make sure you haven't done that.

 

I had this issue. The script was not enabled on GameObject. Spent two hours on searching the solution.

 

I had the same problem because I was disabling the script after spawning it (same frame). This was intentional. Changed it to void Awake instead and now it works.

 

Thanks!

 

I'm currently having this problem in Unity 5.4 where start function isn't being run. I have the script attached to a game controller but I don't see where you can enable or disable a script on that controller. Is there a tick box somewhere that you can activate or deactivate it? The game controller does have a tick box and it is activated.

[UPDATE] I created another TEST script, attached it to the game controller, and just did a debug.log in the start to make sure it works, and that doesn't seem to be working either. This script did have a check box next to it that can be toggled on and off and I have it checked. I have animators attached to the other script so I think that's why the toggle box may not be there?

 

If your component does not have a checkbox on it, that means it does not have any Unity callback methods such as Start(), Update(), FixedUpdate() etc... that care about the enabled/disabled state of the component.

 

Aaaaargh same here! I was also making it worse for myself because Awake() was working but Start() wasn't.

 

Same Hare, I forgot to enable my script.,,,

 

spend 3 hours searching about why get component gave me null, and realized I have lower case 's' for start.

 

Yeah, I've been there, I've done that. And I've done about 57,000 other ways of getting null reference errors.

Here is my shortcut to hammering through nullrefs... hopefully it can save you time too!

--------------------------

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

 

I read all the the "forgot to enable the script" answers but this was the one that made me into retyping all my start and updates and that's when I realized I had Disabled the Canvas the script was attached to instead of just the dialog that it contained that was being referenced by the script. This unity takes a slightly different mindset and slightly different debug strategies than I'm used to (HTML, SQL). Definately stretches the mind.

Thanks all! I'll be Back.

 

I had the same issue, but everything was fine.
My script was attached to the object, was enabled, had the MonoBehaviour class (sometimes can be an issue)...but the problem was other, simple, and frustrating at the same time.

Script 1:

Start()
{
Script2.MethodX();
}


Script 2:
Start()
{
object = new Object();
}

MethodX()
{
object.SetValue();
}

=============
The problem was...the MethodX was called on the Start of Script 1, before Unity calls the Start of Script 2, so the "object" was null. (it was difficult to figure it out, because sometimes it worked and sometimes it didn't)

My solution: Use a coroutine and wait a few frames to call the MethodX on script 1.

I hope if someone have a similar problem, this solution can work.

 

A coroutine is unnecessary. We have the Awake and Start Unity messages for this very reason.

Do self initialisation in Awake, and do anything that requires others objects to be ready in Start.

 

I had this problem too until I realized that I was destroying it in the Awake trying to set up an Instance with Destroy and DontDestroyOnLoad.

 

Same. I wrote "IEnumerable" instead of "IEnumerator" because of vscode autocomplete.

Code (CSharp):

1. private IEnumerator Start(){
2.         Debug.Log("Begin");
3.         yield return new WaitForSeconds(3f);
4.         Debug.Log("End");
5.     }

 

Start() method sometimes can not set component references when it is instantiated. In general Awake method can solve such problems.

 

Thanks alot man I had this problem

 

Read my response after theirs. Use Awake for self-initialisation, Start for initialisation dependant on other objects.

A coroutine is 100% unnecessary.