重启iOS应用后检查相机胶卷中照片是否仍然存在

Question

I'm still new in iOS development and I'm creating an app that allows to select some photos and access them quickly. In CoreData, I store the referenceUrl of the photo instead of the photo itself. I'm able to load photos when starting the app this way.

But, before loading photos, I need to check that they still exist and cannot figure out how to check, using the referenceUrl, if a photo exists or not.

Even using the localPath does not work. It returns false all the time.

If you have any idea how I can proceed, I'll be very grateful. Thanks.

func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {

        let imageUrl          = info[UIImagePickerControllerReferenceURL] as! NSURL
        let imageName         = imageUrl.lastPathComponent
        let documentDirectory = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true).first!
        let photoURL          = NSURL(fileURLWithPath: documentDirectory)
        let localPath         = photoURL.appendingPathComponent(imageName!)!
        let localPathString   = String(describing: localPath)

        let fileManager = FileManager.default
        if fileManager.fileExists(atPath: localPathString){
            print ("Photo exists")
        } else{
            print ("Photo does not exist")
        }
}

Answer 1

I found a solution, here it is.

I use imageUrl from my code above like that:

let assets = PHAsset.fetchAssets(withALAssetURLs: [imageUrl as URL], options: nil)
if assets.firstObject != nil {
   //Then the image is still there
}
else{
   //The image is not present anymore
}

Hope that helps.