Saving image and then loading it in Swift (iOS)

Question

I am saving an image using saveImage.

func saveImage (image: UIImage, path: String ) -> Bool{

    let pngImageData = UIImagePNGRepresentation(image)
    //let jpgImageData = UIImageJPEGRepresentation(image, 1.0)   // if you want to save as JPEG

    print("!!!saving image at:  (path)")

    let result = pngImageData!.writeToFile(path, atomically: true)

    return result
}

New info:

Saving file does not work properly ("[-] ERROR SAVING FILE" is printed)--

            // save your image here into Document Directory
        let res = saveImage(tempImage, path: fileInDocumentsDirectory("abc.png"))
        if(res == true){
            print ("[+] FILE SAVED")
        }else{
            print ("[-] ERROR SAVING FILE")
        }

Why doesn't the saveImage function save the image? Access rights?

Older info:

The debug info says:

!!!saving image at:  file:///var/mobile/Applications/BDB992FB-E378-4719-B7B7-E9A364EEE54B/Documents/tempImage

Then I retrieve this location using

fileInDocumentsDirectory("tempImage")

The result is correct.

Then I am loading the file using this path

    let image = UIImage(contentsOfFile: path)

    if image == nil {

        print("missing image at: (path)")
    }else{
        print("!!!IMAGE FOUND at: (path)")
    }

The path is correct, but the message is "missing image at..". Is the file somehow inaccessible or not stored? What can be a reason for this behavior?

I am testing this code on iphone 4 with ios 7 and iphone 5 with ios 7 simulator.

Edit: 1. The fileInDocumentsDirectory function

func fileInDocumentsDirectory(filename: String) -> String {

    let documentsURL = NSFileManager.defaultManager().URLsForDirectory(.DocumentDirectory, inDomains: .UserDomainMask)[0]
    let fileURL = documentsURL.URLByAppendingPathComponent(filename).absoluteString
    return fileURL        
}

Answer 1

This function will save an image in the documents folder:

func saveImage(image: UIImage) -> Bool {
    guard let data = UIImageJPEGRepresentation(image, 1) ?? UIImagePNGRepresentation(image) else {
        return false
    }
    guard let directory = try? FileManager.default.url(for: .documentDirectory, in: .userDomainMask, appropriateFor: nil, create: false) as NSURL else {
        return false
    }
    do {
        try data.write(to: directory.appendingPathComponent("fileName.png")!)
        return true
    } catch {   
        print(error.localizedDescription)
        return false
    }
}

To use:

let success = saveImage(image: UIImage(named: "image.png")!)

---

This function will get that image:

func getSavedImage(named: String) -> UIImage? {
    if let dir = try? FileManager.default.url(for: .documentDirectory, in: .userDomainMask, appropriateFor: nil, create: false) {
        return UIImage(contentsOfFile: URL(fileURLWithPath: dir.absoluteString).appendingPathComponent(named).path)
    }
    return nil
}

To use:

if let image = getSavedImage(named: "fileName") {
    // do something with image
}