How to fetch Images from CoreData correct? - swift

Question

this is the code how I save images in CoreData:
lazy var dataImage = profileIcon.jpegData(compressionQuality: 1.0)
//MARK: - Saving the Workout Image
func savePUValues() {
// Kontext Identifiziern
guard let appDelegate = UIApplication.shared.delegate as? AppDelegate else {
return
}
let context = appDelegate.persistentContainer.viewContext
let entityName = "PushUps" //Tabellenname im DatenModell
//Neuen Datensatz anlegen:
guard let newEntity = NSEntityDescription.entity(forEntityName: entityName, in: context)
else {
return
}
let newSet = NSManagedObject(entity: newEntity, insertInto: context)
let savingImage = dataImage
newSet.setValue(savingImage, forKey: "image")
// Datensatz speichern
do {
try context.save()
} catch {
print("An error appeared")
}
}
Now I want to fetch the image data and load it into a UITableView:
With this code:
func loadValues() -> [CellData] {
//Kontext identifizieren
let appDelegate = UIApplication.shared.delegate as! AppDelegate
//Anfrage stellen
let context = appDelegate.persistentContainer.viewContext
let entityName = "PushUps"
//MARK: - Request
// Use a specific fetch request
let request = NSFetchRequest<PushUps>(entityName: entityName)
// add a sort descriptor to sort the items by highScore descending
request.sortDescriptors = [NSSortDescriptor(key: "count", ascending: false)]
do {
// results is an array of PushUps instances, no type cast needed
let results = try context.fetch(request)
for r in results {
if let result = r as? NSManagedObject {
let titletext = "\(count!) Push-Ups"
var cellTitleLabel = UILabel()
cellTitleLabel.text = titletext
let workoutImage = result.value(forKey: "image") as? UIImageView
print("Image was loaded into the array")
var Data1 = CellData(imageData: workoutImage ?? oImageView, titleData: cellTitleLabel)
print("Image: \(String(describing: workoutImage)), TitLe: \(cellTitleLabel) ")
cellDataArray.append(Data1)
}
}
} catch {
print(error)
}
return cellDataArray
}
The problem is that the it's loading the image as nil.
The console is giving me this back: "Image: nil, TitLe: <UILabel: 0x115f17980; frame = (0 0; 0 0); text = '0.0 Push-Ups'; userInteractionEnabled = NO; layer = <_UILabelLayer: 0x28249cfa0>> "
So where is the problem? What is wrong with my Code?
Thanks for your help!

Answer 1

The problem is that you are saving Data and trying to retrieve it as a UIImageView, which is doomed to failure:
lazy var dataImage = profileIcon.jpegData(compressionQuality: 1.0)
// Data
let savingImage = dataImage
newSet.setValue(savingImage, forKey: "image")
// still Data
// ---------------------
let workoutImage = result.value(forKey: "image") as? UIImageView
// UIImageView?????
However, don't save image data into Core Data in the first place. Save to disk and store the partial path (e.g. the file name).