Tells the extension to prepare for a host app’s request.
- iOS 10.0+
- UIKit for Mac 13.0+Beta
CXCallobject that represents the context in which the host app makes the request.
Directory Extension Context
An extension prepares for a host app’s request by getting the context passed in this method and requesting related data items, if appropriate. This method is received after the extension is initialized, but before the principal object is asked to do anything with the context.