Resolved: How can I get a reference of a prefab asset from the code in it self?

Question:

So let’s say I have this prefab asset, “P” and have this code attached to it.

public GameObject selfReference;

[ContextMenu("GetReference")]
public void GetReference()
{
    selfReference = gameObject;
}

Note that: the ‘reference finding’ process is trigger by ContextMenu so it is done in Edit Mode, not Play Mode; and all of this is happening in the prefab asset “P” itself, not some random instance of it placed in the scene.
So I tried

selfReference = PrefabUtility.GetNearestPrefabInstanceRoot(gameObject);

but it didn’t work so tried to load it via path:

string _path = AssetDatabase.GetAssetPath(gameObject);

but it returns only blank string.
Any help plz?

Answer:

I can only assume – since it works for me 😉

that your question is rather related to this change not being saved correctly and not being handled for undo/redo.
You should probably do e.g.

public GameObject selfReference;

[ContextMenu(nameof(GetReference))]
public void GetReference()
{
#if UNITY_EDITOR
    if(!Application.isPlaying)
    {
        UnityEditor.Undo.RecordObject(this, "fetched self-reference");

        if (UnityEditor.PrefabUtility.IsPartOfAnyPrefab(this))
        {
            UnityEditor.PrefabUtility.RecordPrefabInstancePropertyModifications(this);
        }
    }
#endif

    selfReference = gameObject;
}

besides that of course it appears a bit redundant to me to have a field for something that is exposed via the property anyway 😉

If you have better answer, please add a comment about this, thank you!