---
title: "QLPreviewRequestFlushContext(_:_:)"
framework: quicklook
role: symbol
role_heading: Function
path: "quicklook/qlpreviewrequestflushcontext(_:_:)"
---

# QLPreviewRequestFlushContext(_:_:)

Flush the context and sets the preview response.

## Declaration

```swift
func QLPreviewRequestFlushContext(_ preview: QLPreviewRequest!, _ context: CGContext!)
```

## Parameters

- `preview`: The preview request object.
- `context`: The graphics context to flush.

## Discussion

Discussion You should call this method immediately after drawing in the graphics contexts created by QLPreviewRequestCreateContext(_:_:_:_:) and QLPreviewRequestCreatePDFContext(_:_:_:_:). Special Considerations Thread-safety: This function should be called in the same thread as the preview request is made in; generally, this is the same thread in which the GeneratePreviewForURL callback was invoked.

## See Also

### Requesting previews

- [QLPreviewRequestCopyContentUTI(_:)](quicklook/qlpreviewrequestcopycontentuti(_:).md)
- [QLPreviewRequestCopyOptions(_:)](quicklook/qlpreviewrequestcopyoptions(_:).md)
- [QLPreviewRequestCopyURL(_:)](quicklook/qlpreviewrequestcopyurl(_:).md)
- [QLPreviewRequestCreateContext(_:_:_:_:)](quicklook/qlpreviewrequestcreatecontext(_:_:_:_:).md)
- [QLPreviewRequestCreatePDFContext(_:_:_:_:)](quicklook/qlpreviewrequestcreatepdfcontext(_:_:_:_:).md)
- [QLPreviewRequestGetDocumentObject(_:)](quicklook/qlpreviewrequestgetdocumentobject(_:).md)
- [QLPreviewRequestSetDocumentObject(_:_:_:)](quicklook/qlpreviewrequestsetdocumentobject(_:_:_:).md)
- [QLPreviewRequestGetGeneratorBundle(_:)](quicklook/qlpreviewrequestgetgeneratorbundle(_:).md)
- [QLPreviewRequestGetTypeID()](quicklook/qlpreviewrequestgettypeid().md)
- [QLPreviewRequestIsCancelled(_:)](quicklook/qlpreviewrequestiscancelled(_:).md)
- [QLPreviewRequestSetDataRepresentation(_:_:_:_:)](quicklook/qlpreviewrequestsetdatarepresentation(_:_:_:_:).md)
- [QLPreviewRequestSetURLRepresentation(_:_:_:_:)](quicklook/qlpreviewrequestseturlrepresentation(_:_:_:_:).md)