---
title: CancelThumbnailGeneration
framework: quicklook
role: symbol
role_heading: Instance Property
path: quicklook/qlgeneratorinterfacestruct/cancelthumbnailgeneration
---

# CancelThumbnailGeneration

## Declaration

```swift
var CancelThumbnailGeneration: ((UnsafeMutableRawPointer?, QLThumbnailRequest?) -> Void)!
```

## See Also

### Creating a Quick Look Plug-In

- [init()](quicklook/qlgeneratorinterfacestruct/init().md)
- [QueryInterface](quicklook/qlgeneratorinterfacestruct/queryinterface.md)
- [AddRef](quicklook/qlgeneratorinterfacestruct/addref.md)
- [Release](quicklook/qlgeneratorinterfacestruct/release.md)
- [GenerateThumbnailForURL](quicklook/qlgeneratorinterfacestruct/generatethumbnailforurl.md)
- [GeneratePreviewForURL](quicklook/qlgeneratorinterfacestruct/generatepreviewforurl.md)
- [CancelPreviewGeneration](quicklook/qlgeneratorinterfacestruct/cancelpreviewgeneration.md)