Instance Method

canAsynchronouslyWriteToURL:ofType:forSaveOperation:

Returns whether the receiver can concurrently write to a file or file package located by a URL, formatted for a specific type, for a specific kind of save operation.

Declaration

- (BOOL)canAsynchronouslyWriteToURL:(NSURL *)url ofType:(NSString *)typeName forSaveOperation:(NSSaveOperationType)saveOperation;

Parameters

url

The location of the file or package to which the document is written.

typeName

The string that identifies the document type.

saveOperation

The type of save operation.

Return Value

NO by default; subclasses can override to return YES, thereby enabling asynchronous writing.

Discussion

The default implementation of this method returns NO. You are strongly encouraged to override it and make it return YES, after making sure your overrides of document writing methods can be safely invoked on a non-main thread, and making sure that the unblockUserInteraction method is invoked at some appropriate time during writing.

See Also

Reading From and Writing to URLs

- readFromURL:ofType:error:

Sets the contents of this document by reading from a file or file package, of a specified type, located by a URL.

- writeToURL:ofType:error:

Writes the contents of the document to a file or file package located by a URL, formatted to a specified type.

- writeSafelyToURL:ofType:forSaveOperation:error:

Writes the contents of the document to a file or file package located by a URL.

- writeToURL:ofType:forSaveOperation:originalContentsURL:error:

Writes the contents of the document to a file or file package located by a URL.

- fileAttributesToWriteToURL:ofType:forSaveOperation:originalContentsURL:error:

As a file is being saved, returns the attributes that should be written to a file or file package located by a URL, formatted to a specified type, for a particular kind of save operation.

- saveToURL:ofType:forSaveOperation:delegate:didSaveSelector:contextInfo:

Saves the contents of the document to a file or file package located by a URL, formatted to a specified type, for a particular kind of save operation.

- changeCountTokenForSaveOperation:

Returns an object that encapsulates the current record of document changes at the beginning of a save operation.

- saveToURL:ofType:forSaveOperation:completionHandler:

Saves the contents of the document to a file or file package located by a URL, formatted to a specified type, for a particular kind of save operation, and invokes the passed-in completion handler.

- updateChangeCountWithToken:forSaveOperation:

Records the fact that saving has succeeded and updates related aspects of the change count mechanism.

- unblockUserInteraction

Unblocks the main thread during asynchronous saving.