documentInteractionControllerWillBeginPreview(_:)
Called when a document interaction controller is about to display a preview for its document.
Declaration
optional func documentInteractionControllerWillBeginPreview(_ controller: UIDocumentInteractionController)Parameters
- controller:
The document interaction controller that is about to preview its document.
Discussion
This method is called shortly before the view containing the document preview is presented modally. You can use this notification to set up any additional interface elements behind the preview elements.