Quick Look UI
Create previews of files to use inside your macOS app.
Overview
When showing files in your app, including the ability to quickly preview a file and its content can be helpful to your users. For example, you may want to allow users to zoom into a photo, play back an audio file, and so on. Use the Quick Look framework to show a preview of common file types in your macOS app that allow basic interactions. Quick Look can generate previews for common file types, including:
iWork and Microsoft Office documents
Images
Live Photos
Text files
PDFs
Audio and video files
You can provide previews for your own data types by either rendering a view with your own view controller or by returning a supported preview format such as PDF or HTML.
Providing Quick Look Previews for your Data Types
To provide Quick Look previews for your own file types, create a Quick Look Preview Extension with either a view controller or data based preview. In either case, add your supported content types to the QLSupportedContentTypes array in the Info.plist file of the extension.
To provide a view controller based preview extension, set up an NSViewController that conforms to QLPreviewingController. Prepare and display the view within the method preparePreviewOfFile(at:completionHandler:).
To provide a data-based preview extension, implement a subclass of QLPreviewProvider to provide a QLPreviewReply based on the QLFilePreviewRequest that the system provides.
Import QuickLookUI to use these extension types in macOS. In iOS and iPadOS, the same types are part of Quick Look, so import QuickLook instead.
Topics
Previews
QLPreviewPanelQLPreviewViewQLPreviewItemQLPreviewPanelDataSourceQLPreviewPanelDelegateQLPreviewItemLoadingBlock