How to send image from framework to sample project in iOS Swift? - ios

Question

I have implemented document scanner using visionKit. Initially i have faced camera dismiss issue and it fixed. Now i am trying to send image after camera dismiss from framework to sample project.
I have tried using completion handler, but it does not work.
Here is the code for framework:
public class A8Scan: NSObject, VNDocumentCameraViewControllerDelegate {
var imageNew: UIImage?
var statusImage: UIImageView?
private var clientView: UIViewController?
public init(_ viewController:UIViewController){
self.clientView = viewController
}
public func showScanner(imgData: UIImage?){
self.createTaskController(img: imgData)
print("Called Build")
}
private func createTaskController(img: UIImage?){
let scannerViewController = VNDocumentCameraViewController()
scannerViewController.delegate = self
self.clientView?.present(scannerViewController,animated:true,completion: {
self.imageNew = img
})
}
public func imageFromFile(result: #escaping (_ image: UIImage?) -> Void){
//the image
let scannerViewController = VNDocumentCameraViewController()
scannerViewController.delegate = self
self.clientView?.present(scannerViewController,animated:true,completion: nil)
if imageNew != nil {
result(imageNew)
}
else{
//callback nil so the app does not pause infinitely if
//the error != nil
result(nil)
}
}
func set(image: UIImage) {
self.statusImage?.image = image
}
public func documentCameraViewController(_ controller: VNDocumentCameraViewController, didFinishWith scan: VNDocumentCameraScan) {
guard scan.pageCount >= 1 else {
controller.dismiss(animated: true)
return
}
let originalImage = scan.imageOfPage(at: 0)
let newImage = compressedImage(originalImage)
imageNew = newImage
set(image: imageNew!)
print("new image::\(newImage.size)")
controller.dismiss(animated: true, completion: nil)
// processImage(newImage)
}
public func documentCameraViewController(_ controller: VNDocumentCameraViewController, didFailWithError error: Error) {
print(error)
controller.dismiss(animated: true)
}
public func documentCameraViewControllerDidCancel(_ controller: VNDocumentCameraViewController) {
controller.dismiss(animated: true)
}
func compressedImage(_ originalImage: UIImage) -> UIImage {
guard let imageData = originalImage.jpegData(compressionQuality: 1),
let reloadedImage = UIImage(data: imageData) else {
return originalImage
}
return reloadedImage
}
}
Here is the code sample project:
#IBAction func btnAction(_ sender: Any) {
// A8Scan(self).showScanner()
// A8Scan(self).showScanner(imgData: im)
// print("nn", A8Scan(self).showScanner(imgData: im))
A8Scan(self).imageFromFile { (image) in
if image != nil {
print(image!)
} else {
print("something went wrong")
}
}
// p()
}
func p (){
ScannerViewController().imageFromFile{(image: UIImage?) -> Void in
//use the image that was just retrieved
print("image data", image)
}
}
My issue is after camera dismiss from framework it does not send image from framework to sample project.
Any help much appreciated pls....

Answer 1

1-
Add this inside your framework
var callBack((UIImage)-())?
public func show() {
let scannerViewController = VNDocumentCameraViewController()
scannerViewController.delegate = self
self.clientView?.present(scannerViewController,animated:true,completion: nil)
}
2-
let newImage = compressedImage(originalImage)
callBack?(newImage)
3-
Then inside the vc that uses it
let vc = A8Scan(self)
vc.show()
vc.callBack = { [weak self] image in
}

Answer 2

As you are using a middle man (A8Scan) NSObject to present a controller. the A8Scan will get deallocated immediately after presenting the controller which you can confirm by keeping a deinit function inside A8Scan.
A workaround for this is to make your NSObject (A8Scan) as a singleton ie add
static let shared = A8Scan()
var callBack: ((_ image: UIImage?) -> Void)?
remove the existing init method and add the viewcontroller property into the imageFromFile: method, your function will look like this
public func imageFromFile(sender: UIViewController, result: #escaping (_ image: UIImage?) -> Void){
let scannerViewController = VNDocumentCameraViewController()
scannerViewController.delegate = self
self.callBack = result
sender.present(scannerViewController,animated:true,completion: nil)
}
public func documentCameraViewController(_ controller: VNDocumentCameraViewController, didFinishWith scan: VNDocumentCameraScan) {
guard scan.pageCount >= 1 else {
controller.dismiss(animated: true)
return
}
let originalImage = scan.imageOfPage(at: 0)
let newImage = compressedImage(originalImage)
imageNew = newImage
set(image: imageNew!)
callBack?(imageNew!)
controller.dismiss(animated: true, completion: nil)
}
and finally in your sample project,
#IBAction func btnAction(_ sender: Any) {
A8Scan.shared.imageFromFile(sender: self) { (image) in
if image != nil {
print(image!)
} else {
print("something went wrong")
}
}
}