The definition of ITEM list below, could you see any problem here? @J0hn
class AlbumItem: Hashable {
let albumURL: URL
let albumTitle: String
let imageItems: [AlbumDetailItem]
init(albumURL: URL, imageItems: [AlbumDetailItem] = []) {
self.albumURL = albumURL
self.albumTitle = albumURL.lastPathComponent.displayNicely
self.imageItems = imageItems
}
func hash(into hasher: inout Hasher) {
hasher.combine(identifier)
}
static func == (lhs: AlbumItem, rhs: AlbumItem) -> Bool {
return lhs.identifier == rhs.identifier
}
private let identifier = UUID()
}
BTW, those unnecessary calling occurs in demo on session 10252，to reproduce this issue:
add delegate for the collection view, disable prefetching to reduce logs:
private func configureHierarchy() {
collectionView = UICollectionView(frame: view.bounds, collectionViewLayout: createLayout())
collectionView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
collectionView.backgroundColor = .systemBackground
// collectionView.prefetchDataSource = self
collectionView.isPrefetchingEnabled = false
collectionView.delegate = self
view.addSubview(collectionView)
}
2. implement the selection callback for removing item from snapshot:
extension PostGridViewController: UICollectionViewDelegate {
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
print("remove items at section:(\(indexPath.section)), item:(\(indexPath.item))")
var snapshot = dataSource.snapshot()
let identfiers = snapshot.itemIdentifiers(inSection: Section.ID.allCases[indexPath.section])
snapshot.deleteItems([identfiers[indexPath.item]])
dataSource.apply(snapshot, animatingDifferences: false)
}
}
finally, remove reload stuff in cell registeration:
let cellRegistration = UICollectionView.CellRegistration<DestinationPostCell, DestinationPost.ID> { [weak self] cell, indexPath, postID in
guard let self = self else { return }
print("configure DestinationPostCell:(\(Unmanaged.passUnretained(cell).toOpaque())) at section:(\(indexPath.section)), item:(\(indexPath.item))")
let post = self.postsStore.fetchByID(postID)
let asset = self.assetsStore.fetchByID(post.assetID)
cell.configureFor(post, using: asset)
}
THEN I ran this demo and clicked the first item to remove it, similar log came out:
configure DestinationPostCell:(0x000000015ef11940) at section:(0), item:(0)
configure DestinationPostCell:(0x000000015ed20410) at section:(0), item:(1)
configure DestinationPostCell:(0x000000015ed21900) at section:(1), item:(0)
remove items at section:(0), item:(0)
configure DestinationPostCell:(0x000000015ed433c0) at section:(1), item:(2)
configure DestinationPostCell:(0x000000015ed433c0) at section:(0), item:(0)
configure DestinationPostCell:(0x000000015ed433c0) at section:(1), item:(0)
configure DestinationPostCell:(0x000000015ed433c0) at section:(1), item:(1)
configure DestinationPostCell:(0x000000015ef11940) at section:(1), item:(1)
