This question was closed Nov 28, 2016 at 10:09 AM by $$anonymous$$ for the following reason:

The question is answered, right answer was accepted

Question by $$anonymous$$ · Nov 26, 2016 at 12:52 PM · c#component instantiation index

First instantiated gameObject`s component is null

Hello guys! Im just instantiating some gameObjects and then editing some variables. So the problem is only with the first instantiated gameObject doesnt have Image Component, while others have.

This is how i instantiate:

 public void constructGrid(int height,int width,Vector2 startPosition, Vector2 Offset)
     {
         nodes = new GameObject[height, width];
         int id = 0;
         for (int i = 0; i < height; i++)
         {
             for (int j = 0; j < width; j++)
             {                
                 nodes[i, j] =  Instantiate(NodePrefab, new Vector3(startPosition.x + j * Offset.x, startPosition.y + Offset.y * i, 1), Quaternion.identity) as GameObject;
                 nodes[i, j].transform.SetParent(transform,false);
                 nodes[i, j].GetComponent<Node>().ID = id;
                 id++;
             }
         }
     }

if i dont check if component is null, then i get null reference exeption on first gameObject in array.

   void Start()
     {          
         if (GetComponent<Image>() == null)
             gameObject.AddComponent<Image>();

            ImageComponent = GetComponent<Image>();          
     }

This is how i check what gameObject has null component, in Debug.Log i get only 0 index which is first element in array.

   void Update()
     {  
         if (GetComponent<Image>() == null)
         {
             Debug.Log(id);
         }            
     }

If i check for null and then add component, than everything works fine, but why does that happen?

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Adam-Mechtley · Nov 28, 2016 at 09:06 AM 0

I don't think I have all the context I need here. Are those Start () and Update () methods both in your Node class, or in a separate class on the same GameObject?