Представление коллекции не перезагружается (Swift)

    class CVController: UICollectionViewController, UINavigationControllerDelegate, UICollectionViewDelegateFlowLayout {

    var photosLibraryArray = [UIImage]()

    override func viewDidLoad() {
    super.viewDidLoad()

        checkPhotoLibraryPermission()
    }

Добавьте эту нижеупомянутую функцию

    func checkPhotoLibraryPermission() {
        let status = PHPhotoLibrary.authorizationStatus()
        switch status {
        case .authorized: 
        //handle authorized status - // call this function here
                grabAllPhotosFromPhoneLibrary()
            case .denied, .restricted : 
                //handle denied status
            case .notDetermined: 
                // ask for permissions
                PHPhotoLibrary.requestAuthorization() { status in
                    switch status {
                    case .authorized: 
                        // call this function here
                        grabAllPhotosFromPhoneLibrary()

                    case .denied, .restricted: 
                        // as above
                        _ = navigationController?.popViewController(animated: true)
                    case .notDetermined: 
                        // won't happen but still, if you want to handle.
                }
        }
    }
    }

Соответственно, вы можете внести изменения в следующую функцию ниже. По необходимости.

    // Grab All Photos from Library
    func grabAllPhotosFromPhoneLibrary () {

    let imageManager = PHImageManager.default()

    let requestOptions = PHImageRequestOptions()
    requestOptions.isSynchronous = true  // synchronous works better when grabbing all images
    requestOptions.deliveryMode = .opportunistic

    let fetchOptions = PHFetchOptions()
    fetchOptions.sortDescriptors = [NSSortDescriptor(key: "creationDate", ascending: true)] // if false = last image we took would show first

    let fetchResult: PHFetchResult = PHAsset.fetchAssets(with: .image, options: fetchOptions)

    // 1. Are there photos in the library
    if fetchResult.count > 0 {

        // 2. if fetch.count > 0 it means there's at least 1 photo in the library
        for i in 0..<fetchResult.count {

            // 3. Cycling through the photos
            imageManager.requestImage(for: fetchResult.object(at: i), targetSize: CGSize(width: 200, height: 200), contentMode: .aspectFill, options: requestOptions, resultHandler:

                { image, error in
                    // 4. Append each image in the array
                    self.photosLibraryArray.append(image!)
            })
        }
    //Use this reload data here as - you want the data loaded in the array first and then show the data.

    self.collectionView?.reloadData()

    } else {
        print("You've got no photos")
        //self.collectionView?.reloadData()

        // if you want to hide the view controller when there is no photo. pop the view controller from your navigation controller like this. 

     _ = navigationController?.popViewController(animated: true)
    }