Import and export annotations from XFDF files on iOS

// Load from an example XFDF file.
let externalAnnotationsFile = URL(fileURLWithPath: "path/to/XFDF.xfdf")

let documentProvider = (document.documentProviders.first)!
let dataProvider = FileDataProvider(fileURL: externalAnnotationsFile)

// Create the XFDF parser and parse all annotations.
let parser = XFDFParser(dataProvider: dataProvider, documentProvider: documentProvider)
let annotations = try! parser.parse()

// Add the parsed annotations to the document.
document.add(annotations: annotations)

// Load from an example XFDF file.
NSURL *externalAnnotationsFile = [NSURL fileURLWithPath:@"path/to/XFDF.xfdf"];

PSPDFDocumentProvider *documentProvider = document.documentProviders.firstObject;
PSPDFFileDataProvider *dataProvider = [[PSPDFFileDataProvider alloc] initWithFileURL:externalAnnotationsFile];

// Create the XFDF parser and parse all annotations.
PSPDFXFDFParser *parser = [[PSPDFXFDFParser alloc] initWithDataProvider:dataProvider documentProvider:documentProvider];
NSArray<PSPDFAnnotation *> *annotations = [parser parseWithError:NULL];

// Add the parsed annotations to the document.
[document addAnnotations:annotations options:nil];

// Collect all existing annotations from the document.
let annotations = document.allAnnotations(of: .all).values.flatMap { $0 }

// Write the file.
let dataSink = try! FileDataSink(fileURL: externalAnnotationsFile)
do {
  try XFDFWriter().write(annotations, to: dataSink, documentProvider: document.documentProviders.first!)
} catch {
  print("Failed to write XFDF file: \(error.localizedDescription))")
}

// Collect all existing annotations from the document.
NSMutableArray<PSPDFAnnotation *> *annotations = [NSMutableArray<PSPDFAnnotation *> array];
for (NSArray<PSPDFAnnotation *> *pageAnnotations in [document allAnnotationsOfType:PSPDFAnnotationTypeAll].allValues) {
  [annotations addObjectsFromArray:pageAnnotations];
}

// Write the file.
NSError *error;
PSPDFFileDataSink *dataSink = [[PSPDFFileDataSink alloc] initWithFileURL:externalAnnotationsFile options:PSPDFDataSinkOptionNone error:&error];
NSAssert(dataSink != nil, @"%@", error);
if (![[PSPDFXFDFWriter new] writeAnnotations:annotations toDataSink:dataSink documentProvider:tempDocument.documentProviders[0] error:&error]) {
  NSLog(@"Failed to write XFDF file: %@", error.localizedDescription);
}

// Load from an example XFDF file.
let externalAnnotationsFile = URL(fileURLWithPath: "path/to/XFDF.xfdf")

// Create `document` and set up the XFDF provider.
let document = Document()
document.annotationSaveMode = .externalFile
document.didCreateDocumentProviderBlock = { documentProvider in
  let XFDFProvider = XFDFAnnotationProvider(documentProvider: documentProvider, fileURL: externalAnnotationsFile)
  documentProvider.annotationManager.annotationProviders = [XFDFProvider]
}

// Load from an example XFDF file.
NSURL *externalAnnotationsFile = [NSURL fileURLWithPath:@"path/to/XFDF.xfdf"];

// Create `document` and set up the XFDF provider.
PSPDFDocument *document = [[PSPDFDocument alloc] initWithURL:documentURL];
document.annotationSaveMode = PSPDFAnnotationSaveModeExternalFile;
document.didCreateDocumentProviderBlock = ^(PSPDFDocumentProvider *documentProvider) {
  PSPDFXFDFAnnotationProvider *XFDFProvider = [[PSPDFXFDFAnnotationProvider alloc] initWithDocumentProvider:documentProvider fileURL:externalAnnotationsFile];
  documentProvider.annotationManager.annotationProviders = @[XFDFProvider];
};

// Where `document` is a `Document` instance.
SDK.shared.cache.remove(for: document)

// Where `document` is a `PSPDFDocument` instance.
[PSPDFKitGlobal.sharedInstance.cache removeCacheForDocument:document];