Returns the NSDocument objects managed by the receiver. If there are currently no documents, returns an empty NSArray. The first string in the returned NSArray is typically the most common extension. The array may also contain encoded HFS file types as will as file name extensions. Each file in the returned NSArray is a fully qualified path to the file's location in the file system.
Returns null if the user cancels the Open panel or makes no selection.
Creates and returns an NSDocument object for document type docType from the contents of the file fileName , which must be a fully qualified path. Returns null if the NSDocument subclass for docType couldn't be determined or if the object couldn't be created. This method is invoked by openDocumentWithContentsOfFile . Creates and returns an NSDocument object for document type docType from the contents of anURL . Returns null if the NSDocument subclass for docType couldn't be determined or if the object couldn't be created.