metatext/Data Sources/CompositionAttachmentsDataSource.swift
Justin Mazzocchi 86b9e4c903
wip
2020-12-31 16:49:59 -08:00

33 lines
1.3 KiB
Swift

// Copyright © 2020 Metabolist. All rights reserved.
import Mastodon
import UIKit
import ViewModels
final class CompositionAttachmentsDataSource: UICollectionViewDiffableDataSource<Int, Attachment> {
private let updateQueue =
DispatchQueue(label: "com.metabolist.metatext.composition-attachments-data-source.update-queue")
init(collectionView: UICollectionView,
viewModelProvider: @escaping (IndexPath) -> CompositionAttachmentViewModel?) {
let registration = UICollectionView.CellRegistration
<CompositionAttachmentCollectionViewCell, CompositionAttachmentViewModel> {
$0.viewModel = $2
}
super.init(collectionView: collectionView) { collectionView, indexPath, _ in
collectionView.dequeueConfiguredReusableCell(
using: registration,
for: indexPath,
item: viewModelProvider(indexPath))
}
}
override func apply(_ snapshot: NSDiffableDataSourceSnapshot<Int, Attachment>,
animatingDifferences: Bool = true,
completion: (() -> Void)? = nil) {
updateQueue.async {
super.apply(snapshot, animatingDifferences: animatingDifferences, completion: completion)
}
}
}