# TrickleDown

> Callback reacts during the TrickleDown phase. If not set, callback reacts during the BubbleUp phase.

## Definition

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

```csharp
TrickleDown = 1
```