Unable to save pdf after signature - ios

Question

I am able to sign a pdf, But when I tried to saved it, Its not saving the updated pdf file.
Code
override func viewDidAppear(_ animated: Bool) {
pdfContainerView.usePageViewController(true, withViewOptions: nil)
guard let signatureImage = signatureImage, let page = pdfContainerView.currentPage else { return }
let pageBounds = page.bounds(for: .cropBox)
let imageBounds = CGRect(x: pageBounds.midX, y: pageBounds.midY, width: 200, height: 100)
let imageStamp = ImageStampAnnotation(with: signatureImage, forBounds: imageBounds, withProperties: nil)
page.addAnnotation(imageStamp)
btnSaveSign.isHidden = false
}
func setupPdfView(url:String) {
if let documentURL = URL(string: url),
let data = try? Data(contentsOf: documentURL),
let document = PDFDocument(data: data) {
// Set document to the view, center it, and set background color
//pdfContainerView.displayMode = .singlePageContinuous
pdfContainerView.document = document
pdfContainerView.autoScales = true
pdfContainerView.displayDirection = .horizontal
pdfContainerView.backgroundColor = UIColor.white
btnNewSign.isHidden = false
lblPlaceholder.isHidden = true
let panAnnotationGesture = UIPanGestureRecognizer(target: self, action: #selector(didPanAnnotation(sender:)))
pdfContainerView.addGestureRecognizer(panAnnotationGesture)
}
}
#objc func didPanAnnotation(sender: UIPanGestureRecognizer) {
let touchLocation = sender.location(in: pdfContainerView)
guard let page = pdfContainerView.page(for: touchLocation, nearest: true)
else {
return
}
let locationOnPage = pdfContainerView.convert(touchLocation, to: page)
switch sender.state {
case .began:
guard let annotation = page.annotation(at: locationOnPage) else {
return
}
if annotation.isKind(of: ImageStampAnnotation.self) {
currentlySelectedAnnotation = annotation
}
case .changed:
guard let annotation = currentlySelectedAnnotation else {
return
}
let initialBounds = annotation.bounds
// Set the center of the annotation to the spot of our finger
annotation.bounds = CGRect(x: locationOnPage.x - (initialBounds.width / 2), y: locationOnPage.y - (initialBounds.height / 2), width: initialBounds.width, height: initialBounds.height)
//print("move to \(locationOnPage)")
case .ended, .cancelled, .failed:
currentlySelectedAnnotation = nil
default:
break
}
}
#objc func clickButton(){
let importMenu = UIDocumentPickerViewController(documentTypes: [String(kUTTypePDF)], in: .import)
importMenu.delegate = self
importMenu.modalPresentationStyle = .formSheet
self.present(importMenu, animated: true, completion: nil)
}
public func documentPicker(_ controller: UIDocumentPickerViewController, didPickDocumentsAt urls: [URL]) {
guard let myURL = urls.first else {
return
}
print("import result : \(myURL)")
self.pdfURLToSave = "\(myURL)"
let pdfView = PDFView(frame: view.frame)
title = "My PDF Viewer"
setupPdfView(url:"\(myURL)")
}
func documentInteractionControllerViewControllerForPreview(_ controller: UIDocumentInteractionController) -> UIViewController {
return self//or use return self.navigationController for fetching app navigation bar colour
}
public func documentMenu(_ documentMenu:UIDocumentPickerViewController, didPickDocumentPicker documentPicker: UIDocumentPickerViewController) {
documentPicker.delegate = self
present(documentPicker, animated: true, completion: nil)
}
Code snippet for save file-
#IBAction func btnSaveAction(_ sender: Any) {
if let documentURL = URL(string: self.pdfURLToSave),
let data = try? Data(contentsOf: documentURL),
let document = PDFDocument(data: data) {
if let data = document.dataRepresentation(){
let paths = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)
let documentsDirectory = paths[0] // Get documents folder
let folderPathUrl = URL(fileURLWithPath: documentsDirectory).appendingPathComponent("SignApp.pdf")
if FileManager.default.fileExists(atPath: folderPathUrl.path){
try? FileManager.default.removeItem(at: folderPathUrl)
}
pdfContainerView.document?.write(toFile: "\(folderPathUrl)")
}
}
}
ImageStampAnnotation Class
class ImageStampAnnotation: PDFAnnotation {
var image: UIImage!
// A custom init that sets the type to Stamp on default and assigns our Image variable
init(with image: UIImage!, forBounds bounds: CGRect, withProperties properties: [AnyHashable : Any]?) {
super.init(bounds: bounds, forType: PDFAnnotationSubtype.stamp, withProperties: properties)
self.image = image
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
override func draw(with box: PDFDisplayBox, in context: CGContext) {
// Get the CGImage of our image
guard let cgImage = self.image.cgImage else { return }
// Draw our CGImage in the context of our PDFAnnotation bounds
context.draw(cgImage, in: self.bounds)
}
}
Error-
CGPDFContextCreate: failed to create PDF context delegate..
App screen shots-

Answer 1

It's not possible for me to edit your code directly to show a proper solution, since your code isn't complete, but here is a short coordinator class, including your pan annotation code that saves an updated file each time a pan gesture is completed:
class Coordinator : NSObject {
var pdfView : PDFView?
var currentlySelectedAnnotation : PDFAnnotation?
func getDocumentsDirectory() -> URL {
let paths = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)
let documentsDirectory = paths[0]
return documentsDirectory
}
func save() {
guard let pdfView = pdfView else {
return
}
let url = getDocumentsDirectory().appendingPathComponent("SavedPDF.pdf")
pdfView.document?.write(to: url)
print("Wrote pdf to: ", url)
}
#objc func didPanAnnotation(sender: UIPanGestureRecognizer) {
guard let pdfContainerView = pdfView else {
fatalError()
}
let touchLocation = sender.location(in: pdfContainerView)
guard let page = pdfContainerView.page(for: touchLocation, nearest: true)
else {
return
}
let locationOnPage = pdfContainerView.convert(touchLocation, to: page)
switch sender.state {
case .began:
guard let annotation = page.annotation(at: locationOnPage) else {
return
}
print("Set")
if annotation.isKind(of: ImageStampAnnotation.self) {
currentlySelectedAnnotation = annotation
}
case .changed:
guard let annotation = currentlySelectedAnnotation else {
return
}
let initialBounds = annotation.bounds
// Set the center of the annotation to the spot of our finger
annotation.bounds = CGRect(x: locationOnPage.x - (initialBounds.width / 2), y: locationOnPage.y - (initialBounds.height / 2), width: initialBounds.width, height: initialBounds.height)
//print("move to \(locationOnPage)")
case .ended, .cancelled, .failed:
currentlySelectedAnnotation = nil
save()
default:
break
}
}
}
For context, if it helps, this is how I set up the view controller and the PDFView initially:
let vc = UIViewController()
let pdfContainerView = PDFView()
let fileUrl = Bundle.main.url(forResource: "High Noon - SCORE", withExtension: "pdf")!
let pdfDocument = PDFDocument(url: fileUrl)
pdfContainerView.document = pdfDocument
pdfContainerView.autoScales = true
vc.view.addSubview(pdfContainerView)
let panAnnotationGesture = UIPanGestureRecognizer(target: context.coordinator, action: #selector(context.coordinator.didPanAnnotation(sender:)))
pdfContainerView.addGestureRecognizer(panAnnotationGesture)
let page = pdfContainerView.currentPage!
let pageBounds = page.bounds(for: .cropBox)
let imageBounds = CGRect(x: pageBounds.midX, y: pageBounds.midY, width: 200, height: 100)
let imageStamp = ImageStampAnnotation(with: UIImage(systemName: "pencil"), forBounds: imageBounds, withProperties: nil)
page.addAnnotation(imageStamp)