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// A bit on Unity 3D null handling  ｱｷﾀ━━━(#ﾟДﾟ)━━━!!!!
 
// cached references to items needing refresh; items implementing IRefreshable all derived from MonoBehaviour
static List<IRefreshable> refreshListeners = new List<IRefreshable>();
 
//...
 
    public void OnClick() {
        AnalyzeItemHelper.Analyze(item);        // do some logic
        for(int i=0; i<refreshListeners.Count; i++) {       // ...and notify listeners about change
            if(refreshListeners[i] != null) {       // ensure listeners didn't forget to deregister themselves
                // the problem is we actually reach that line even if SomeListener listener == null
                refreshListeners[i].Refresh();
            } else Debug.LogWarning("One of the refresh listeners is null!");
        }
    }
 
//---- IRefreshable.Refresh implementation of one of the listeners
    void Refresh {
        if(this == null) return;        // without this line it goes further and further, and finally throws MissingReferenceException in some random place...
        itemsView.Refresh();
        // ...
    }
 
/*
 
the problem is caused by the fact UnityEngine.Object overrides equality operators, so if the underlying C object no longer exists (e.g. was destroyed explicitly, or the scene was unloaded) the someUnityObject == null comparison returns true.
But in this code I relied on interfaces, since there was a lot of different things that needed to be notified that given item was analyzed. IRefreshable does not override equality operators, so for the check refreshListeners[i] was not null...
 
all hail unity ー_ー;
 
*/