---
title: FxUndoAPI
framework: Professional Video Applications
role: symbol
role_heading: Protocol
platforms: [fxplug 3.1+]
path: professional_video_applications/fxundoapi
---

# FxUndoAPI

An API that defines the methods that the host app implements to handle plug-in management of the host app’s undo queue.

## Declaration

```swift
protocol FxUndoAPI
```

## Overview

Overview Note that not all host apps implement this protocol.

## Topics

### Creating Undo Groups

- [startUndoGroup(_:)](professional_video_applications/fxundoapi/startundogroup(_:).md)
- [endUndoGroup()](professional_video_applications/fxundoapi/endundogroup().md)

## See Also

### User interface

- [Adding parameters to plug-ins](professional-video-applications/adding-parameters-to-plug-ins.md)
- [Adding onscreen controls to plug-ins](professional-video-applications/adding-onscreen-controls-to-plug-ins.md)
- [FxPathAPI_v3](professional_video_applications/fxpathapi_v3.md)
- [FxCommandAPI](professional_video_applications/fxcommandapi.md)
- [FxCommandAPI_v2](professional_video_applications/fxcommandapi_v2.md)
- [FxRemoteWindowAPI](professional_video_applications/fxremotewindowapi.md)
- [FxRemoteWindowAPI_v2](professional_video_applications/fxremotewindowapi_v2.md)