create gameobject via script and change it's color doesn't work

Unity Engine
1

Hey,
I create a GameObject with a prefab:

GameObject cube_prefab = (GameObject)Resources.Load("FiniteElement", typeof(GameObject));
GameObject new_cube = Instantiate(cube_prefab,new Vector3(x,y,0),Quaternion.identity);
FinitElement fe = new_cube.GetComponent<FinitElement>(); // get the script of the instantiated object
fe.setBaseType(FinitElement.BaseType.core); // call the method of the script (this works, I tested it with print())

After creating, I have to declare some variables of this instantiate, e.g. the “BaseType”. I don’t want to do this directly, but with a method. The reason is that later I can center other things in this methods, e.g. changing the material at the same moment.

The Method in the Script, which is attached on the prefab is:

public class FinitElement : MonoBehaviour
{
  public enum BaseType {core, rock, soil, water, air}
  public BaseType myBaseType = BaseType.air;
  private Renderer myRenderer;
  void Start()
  {
    myRenderer = GetComponent<Renderer>();myRenderer.material.color = Color.yellow;
  }
  public void setBaseType(BaseType _BaseType)  // <- this is the method
  {
    myBaseType = _BaseType;
    myRenderer.material.color = Color.yellow; // for testing just a test with the material color
  }
}

I get an error " NullReferenceException: Object reference not set to an instance of an object FinitElement.setBaseType (BaseType _BaseType)"
Which is produced by the last lin in void setBaseType: myRenderer.material.color = Color.yellow;.
If I comment this out, the engine starts - but of course not with the needed effect.
I can’t figure out, what is wrong with my attempt to save the Renderer in myRenderer and acessing it later in the method setBaseType.
Can anyone give me a hint?

2

Most likely setBaseType is being called before Start() has been called, so myRenderer is null. That, or you don’t have a renderer component attached to this particular GameObject.

3

Thanks, the first suggestion was right! I changed Start() to Awake() and it worked!

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