# source

> The object that started the drag.

## Definition

* **Type:** Property
* **Namespace:** [UnityEngine.UIElements](/engine/6000.6/script-reference/unityengine/uielements.md)
* **Assembly:** UnityEngine.UIElementsModule

```csharp
public abstract object source { get; }
```

### Remarks

For collection views such as [ListView](/engine/6000.6/script-reference/unityengine/uielements/listview.md), [TreeView](/engine/6000.6/script-reference/unityengine/uielements/treeview.md), and others, this refers to the corresponding view that started the drag-and-drop.