# UnregisterReferenceUnloadedCallback(Action<T>)

> Unregisters a callback for when the referenced object is unloaded.

## Definition

* **Type:** Method
* **Namespace:** [UnityEngine.UIElements](/engine/6000.5/script-reference/unityengine/uielements.md)
* **Assembly:** UnityEngine.UIElementsModule

```csharp
public void UnregisterReferenceUnloadedCallback(Action<T> callback)
```

### Parameters

**** (\[Action\<T>]\(https\://learn.microsoft.com/dotnet/api/system.action-1)): The callback to unregister.