changeCountToken(for:)
Returns an object that encapsulates the current record of document changes at the beginning of a save operation.
Declaration
func changeCountToken(for saveOperation: NSDocument.SaveOperationType) -> AnyParameters
- saveOperation:
The type of save operation.
Return Value
An object encapsulating the document changes.
Discussion
The returned object is meant to be passed to updateChangeCount(withToken:for:) at the end of the save operation. For example, save(to:ofType:for:completionHandler:) invokes this method, on the main thread, before it does any actual saving. This method facilitates asynchronous saving, during which a user can change a document while it is being saved.