Swift: Saving photos to CoreData - ios

Question

I need to save images downloaded from the Internet to CoreData.
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return photos.count
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "collectionPhotoCell", for: indexPath) as! PhotoCollectionCell
let photo = photos[(indexPath as NSIndexPath).row]
if let getImage = photo.getImage() {
cell.photoImageView.image = getImage
}
else {
// Photo Placeholder
cell.photoImageView.image = UIImage(named: "imgPlaceholder.png")
// Activity Indicator
cell.activityIndicator.isHidden = false
cell.activityIndicator.startAnimating()
FlickrClient().imageData(photo) {
(imageData, error) in
guard error == nil else {
return
}
DispatchQueue.main.async {
cell.activityIndicator.isHidden = true
cell.activityIndicator.stopAnimating()
cell.photoImageView.image = UIImage(data: imageData!)
}
}
}
cell.photoImageView.alpha = 1.0
return cell
}
Update:
In CoreData, the entity is Photos, and the Attribute is imageData. Looking at the code below, how does managedObjectContext.save(), save the downloaded images (in the collectionView) to CoreData? I'm still confused.
let photos = NSEntityDescription.insertNewObjectForEntityForName("Photo", inManagedObjectContext: self.managedObjectContext!) as Photo
do {
try managedObjectContext.save()
} catch {
fatalError("Failure to save")
}

Answer 1

You can get the managed object context from AppDelegate in this way:
let appDelegate = UIApplication.shared.delegate as! AppDelegate
let managedObjectContext = appDelegate.persistentContainer.viewContext

Answer 2

Step 1:-
first we have to find image's path into your simulator's document directory using
let documentsDirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first!
let fileURL = documentsDirectory.appendingPathComponent("image.png")
print(fileURL)
if let data = image.pngData() {
do {
try data.write(to: fileURL)
let imgPath = "\(fileURL)"
imgCategoryPath = imgPath
} catch {
print("error saving file to documents:", error)
}
Step 2:-
second we have to retrive that image path from your simulator's document directory using
let nsDocumentDirectory = FileManager.SearchPathDirectory.documentDirectory
let nsUserDomainMask = FileManager.SearchPathDomainMask.userDomainMask
let paths = NSSearchPathForDirectoriesInDomains(nsDocumentDirectory, nsUserDomainMask, true)
if let dirPath = paths.first{
let imageURL = URL(fileURLWithPath: dirPath).appendingPathComponent(nameOfImage).absoluteString
print(imageURL)
}
which path has got that store into core data in string formate column
Set Data
do {
try context.write(imageURL)
} catch {
print(error)
}
Read Data
do {
let imgString = try context.read(imageURL)
} catch {
print(error)
}