Custom
Caller-supplied absolute path. Two shapes are accepted:
Full file path — pass an empty string for
filenamein PdfDocument.save. The library writes the bytes to path verbatim.Directory path — pass a non-empty
filename. The library joinspathandfilenamewith a/and writes there.
Parent directories are created automatically if missing. Use this when a path comes from a system picker (ACTION_CREATE_DOCUMENT on Android, UIDocumentPickerViewController on iOS) or from configuration.