Issues instantiating a game object

Questions & Answers
1

Hello, I am instantiating a list of UI game objects. But when I start the game I get a

null reference exception: object
reference not set to an instance of an
object

Here is my code:

    public class MyClass: Monobehaviour
    {
        public GameObject ObjectiveTextPrefab;
        private GameObject _objectiveListInstance;
        
            void Start()
            {
                _data = GameData.Instance.LoadData();
               
                var stats = _data.Scenarios.FirstOrDefault(t => t.Name == Scenario.ToString());
        
                for (int i = 0; i < stats.MyObjectives.Length; i++)
                {
                    _objectiveListInstance = Instantiate(ObjectiveTextPrefab);
                    _objectiveListInstance.transform.SetParent(objectivesListParent, false);
                    _objectiveListInstance.transform.Find("ObjectiveText").GetComponent<Text>().text = stats.MyObjectives*.Title;*

_objectiveListInstance.transform.Find(“Counter”).GetComponent().text = stats.MyObjectives*.Count.ToString();*

}
}
void OnEnable()
{
_data = GameData.Instance.LoadData();

var stats = _data.Scenarios.FirstOrDefault(t => t.Name == Scenario.ToString());

for (int i = 0; i < stats.MyObjectives.Length; i++)
{
if (stats.MyObjectives*.Active)*
{
_objectiveListInstance.transform.Find(“Counter”).GetComponent().color = Color.yellow;
_objectiveListInstance.transform.Find(“ObjectiveText”).GetComponent().color = Color.yellow;
}
else
{
_objectiveListInstance.transform.Find(“ObjectiveText”).GetComponent().color = Color.white;
_objectiveListInstance.transform.Find(“Counter”).GetComponent().color = Color.white;
}

if (stats.MyObjectives*.Active)*
{
_objectiveListInstance.transform.Find(“Counter”).GetComponent().color = Color.yellow;
_objectiveListInstance.transform.Find(“ObjectiveText”).GetComponent().color = Color.yellow;
}
else
{
_objectiveListInstance.transform.Find(“ObjectiveText”).GetComponent().color = Color.white;
_objectiveListInstance.transform.Find(“Counter”).GetComponent().color = Color.white;
}

if (stats.MyObjectives*.Completed)*
{
_objectiveListInstance.transform.Find(“Toggle”).GetComponent().isOn = true;
_objectiveListInstance.transform.Find(“ObjectiveText”).GetComponent().color = Color.gray;
_objectiveListInstance.transform.Find(“Counter”).GetComponent().color = Color.gray;
}
else
{
_objectiveListInstance.transform.Find(“Toggle”).GetComponent().isOn = false;
}
}
}

}
The error points to the _objectiveListInstance variable found in the OnEnable() function. It says that it is null. Can someone help me understand why I am getting this issue? Many thanks in advance!

2

You’re assining your _objectiveListInstance at the Start(); but OnEnable is called before that:

OnEnable will be called again if you Active and Deactive your object, but if he starts active OnEnable() will be before the Start();