Requesting help with "UnassignedReferenceException" error

I'm getting this error on startup:

I have dudeTemplate exposed at the top of LevelScript.js:

Code (csharp):

1. var dudeTemplate:GameObject;

...and I've dragged and dropped a game object onto it in the Inspector. What's really weird is that I use spacerTemplate to spawn objects later in the level, and it seems to work fine despite the error message. After searching the forums I tried making the dudeTemplate game object a prefab, but that didn't change anything so I reverted it.

Here's the code:

Code (csharp):

1.  
2. var dudeTemplate:GameObject;
3.  
4. private var dudeSpawns:Array;
5.  
6. function Start() {
7.     SpawnDudes();
8. }
9.  
10. function SpawnDudes() {
11.     dudeSpawns = GameObject.FindGameObjectsWithTag("dudespawn");
12.  
13.     for(var ds:GameObject in dudeSpawns ) {
14.         Instantiate(dudeTemplate, ds.transform.position, ds.transform.rotation);
15.     }
16. }

What's really weird is that looking at the console output (I have Debug.Logs sprinkled through that I omitted here) it appears that SpawnDudes() is getting called twice. The first time finds my three "dudespawn" objects and succesfully spawns a dudeTemplate on each. But then it immediately gets called again (I have no idea why that would be... I have just one call to it in Start()) and it throws the NullReferenceException when trying to spawn the second dudeTemplate for the second time.

I must be missing something! Can anyone help?

 

You've attached the script to two things.

In Start, Debug.Log( gameObject.name + ", child of " + transform.parent.name ) and you can see which two objects are calling the function.

 

OK, I fixed it with:

Code (csharp):

1.  
2. if(dudeTemplate)
3.     Instantiate(dudeTemplate, ds.transform.position, ds.transform.rotation);

...which gets rid of the error (yay!), but I still don't know why it was an error in the first place. I'm guessing order of operations - maybe I'm trying to Instantiate dudeTemplate for its properly initialized? Also, the order of msgs in the console doesn't seem guaranteed (?) which could also be confusing me... hmm I really should timestamp my debug logs.

Finally, I noted that all the Instantiate examples in the documentation assign the return value, like this:

Code (csharp):

1. var rocketClone : Rigidbody = Instantiate(rocket, transform.position, transform.rotation);

...but I'm not doing that since I have no need of it. Could that be causing a problem (I don't see why it would... but not much of this is making sense to me right now)

 

Hmm, thanks let me check that out...

OK, I pasted that line in at the top of Start(), and it didn't seem to work. I get:

..although I get it twice which supports your theory. I wonder if I accidentally dropped my LevelScript.js on something in the Hierarchy or Project window...

 

Well look at that, you were absolutely right Vicenti. I had somehow attached my LevelScript to a completely spurious object. I deleted the duplicate and I'm all good.

Thanks a bunch for the help, that was awesome.

 

Ah, sorry, the culprit was the 'transform.parent' in mine; since your objects didn't have parent that threw an exception >_<

Glad to be of help, though.