---
title: QLThumbnailProvider
framework: quicklookthumbnailing
role: symbol
role_heading: Class
path: quicklookthumbnailing/qlthumbnailprovider
---

# QLThumbnailProvider

An abstract base class for creating thumbnails of custom file types.

## Declaration

```swift
class QLThumbnailProvider
```

## Mentioned in

Providing Thumbnails of Your Custom File Types

## Topics

### Essentials

- [provideThumbnail(for:_:)](quicklookthumbnailing/qlthumbnailprovider/providethumbnail(for:_:).md)

## Relationships

### Inherits From

- [NSObject](objectivec/nsobject-swift.class.md)

### Conforms To

- [CVarArg](swift/cvararg.md)
- [CustomDebugStringConvertible](swift/customdebugstringconvertible.md)
- [CustomStringConvertible](swift/customstringconvertible.md)
- [Equatable](swift/equatable.md)
- [Hashable](swift/hashable.md)
- [NSObjectProtocol](objectivec/nsobjectprotocol.md)

## See Also

### Thumbnails for Custom File Types

- [Providing Thumbnails of Your Custom File Types](quicklookthumbnailing/providing-thumbnails-of-your-custom-file-types.md)
- [QLFileThumbnailRequest](quicklookthumbnailing/qlfilethumbnailrequest.md)
- [QLThumbnailReply](quicklookthumbnailing/qlthumbnailreply.md)