How to access objects by reference stored in array?

Questions & Answers
1

Hello! I dynamically create (during run-time) a set of objects and supposedly store references to them in a two-dimensional array. When I try to get one of stored object through a public method (by call from another script if it matters) I get NULL. Perhaps I’m missing something about scopes or what the heck is going on? Field property contains prefab.

public class Field : MonoBehaviour {
      public GameObject field;
      private GameObject[,] FieldSet = new GameObject[5,5];
    
      void Start () {
        for (int _i = 0; _i < 5; _i++)
    	{
    	  for (int _j = 0; _j < 5; _j++)
    	  {
    	    FieldSet[_i, _j] = Instantiate(field);
    	    print(FieldSet[_i, _j]);  // prints "field clone"
    	  }
    	}	
      }
    
      public void ShowField(int a, int b){      //a = 1, b = 2
         print(FieldSet[a,b]);  //    prints "NULL"
      }
    }
2

@Williamsii
Your script works fine. I added an Update method to the class and iterated through all game objects in the field set printing out their name (using Debug.Log). Are you sure that “public GameObject field” is initialized?

public GameObject field;
private GameObject[,] FieldSet = new GameObject[5,5];
private bool initialized = false;

void Start ()
{
    for (int _i = 0; _i < 5; _i++)
    {
        for (int _j = 0; _j < 5; _j++)
        {
            FieldSet[_i, _j] = Instantiate(field);
        }
    }    
}

public void Update()
{
    if (!initialized)
    {
        initialized = true;
        for (int _i = 0; _i < 5; _i++)
        {
            for (int _j = 0; _j < 5; _j++)
            {
                ShowField(_i, _j);
            }
        }    
    }    
}

public void ShowField(int a, int b)
{
    if (FieldSet[a, b] != null)
    {
        Debug.Log("Field[" + a + "][" + b + "].name = " + FieldSet[a, b].name);
    }
    else
    {
        Debug.Log("Field[" + a + "][" + b + "] = " + null);
    }
}

Field[0][0].name = Field(Clone)
Field[0][1].name = Field(Clone)
Field[0][2].name = Field(Clone)
Field[0][3].name = Field(Clone)
Field[0][4].name = Field(Clone)
Field[1][0].name = Field(Clone)
Field[1][1].name = Field(Clone)
Field[1][2].name = Field(Clone)
Field[1][3].name = Field(Clone)
Field[1][4].name = Field(Clone)
Field[2][0].name = Field(Clone)
Field[2][1].name = Field(Clone)
Field[2][2].name = Field(Clone)
Field[2][3].name = Field(Clone)
Field[2][4].name = Field(Clone)
Field[3][0].name = Field(Clone)
Field[3][1].name = Field(Clone)
Field[3][2].name = Field(Clone)
Field[3][3].name = Field(Clone)
Field[3][4].name = Field(Clone)
Field[4][0].name = Field(Clone)
Field[4][1].name = Field(Clone)
Field[4][2].name = Field(Clone)
Field[4][3].name = Field(Clone)
Field[4][4].name = Field(Clone)