Why is my UICollectionView not loading cells? - uicollectionview

Question

I have a view controller in my app that plays user videos and you can scroll to the right to go to the next video. I have a cell set up that loads the video from the URL in firebase storage and loads the other data. Here is the cell code:
import UIKit
import AVFoundation
protocol ClipsCollectionViewCellDelegate: AnyObject {
func didTapProfile(with model: VideoModel)
func didTapShare(with model: VideoModel)
func didTapNewClip(with model: VideoModel)
}
class ClipsCollectionViewCell: UICollectionViewCell {
static let identifier = "ClipsCollectionViewCell"
// Labels
private let usernameLabel: UILabel = {
let label = UILabel()
label.textAlignment = .center
label.textColor = UIColor.systemPink.withAlphaComponent(0.5)
label.backgroundColor = UIColor.systemPink.withAlphaComponent(0.1)
label.clipsToBounds = true
label.layer.cornerRadius = 8
return label
}()
// Buttons
private let profileButton: UIButton = {
let button = UIButton()
button.setBackgroundImage(UIImage(systemName: "person.circle"), for: .normal)
button.tintColor = .white
button.backgroundColor = UIColor.systemBlue.withAlphaComponent(0.1)
button.clipsToBounds = true
button.layer.cornerRadius = 32
button.isUserInteractionEnabled = true
return button
}()
private let shareButton: UIButton = {
let button = UIButton()
button.setBackgroundImage(UIImage(systemName: "square.and.arrow.down"), for: .normal)
button.tintColor = .white
button.backgroundColor = UIColor.systemBlue.withAlphaComponent(0.1)
button.clipsToBounds = true
button.layer.cornerRadius = 4
button.isUserInteractionEnabled = true
return button
}()
private let newClipButton: UIButton = {
let button = UIButton()
button.setBackgroundImage(UIImage(systemName: "plus"), for: .normal)
button.tintColor = .systemOrange
button.backgroundColor = UIColor.systemOrange.withAlphaComponent(0.1)
button.clipsToBounds = true
button.layer.cornerRadius = 25
button.isUserInteractionEnabled = true
return button
}()
private let videoContainer = UIView()
// Delegate
weak var delegate: ClipsCollectionViewCellDelegate?
// Subviews
var player: AVPlayer?
private var model: VideoModel?
override init(frame: CGRect) {
super.init(frame: frame)
contentView.backgroundColor = .black
contentView.clipsToBounds = true
addSubviews()
}
private func addSubviews() {
contentView.addSubview(videoContainer)
contentView.addSubview(usernameLabel)
contentView.addSubview(profileButton)
contentView.addSubview(shareButton)
contentView.addSubview(newClipButton)
// Add actions
profileButton.addTarget(self, action: #selector(didTapProfileButton), for: .touchUpInside)
shareButton.addTarget(self, action: #selector(didTapShareButton), for: .touchUpInside)
newClipButton.addTarget(self, action: #selector(didTapNewClipButton), for: .touchUpInside)
videoContainer.clipsToBounds = true
contentView.sendSubviewToBack(videoContainer)
}
#objc private func didTapProfileButton() {
guard let model = model else {
return
}
delegate?.didTapProfile(with: model)
}
#objc private func didTapShareButton() {
guard let model = model else {
return
}
delegate?.didTapShare(with: model)
}
#objc private func didTapNewClipButton() {
guard let model = model else {
return
}
delegate?.didTapNewClip(with: model)
}
override func layoutSubviews() {
super.layoutSubviews()
videoContainer.frame = contentView.bounds
let size = contentView.frame.size.width/7
let width = contentView.frame.size.width
let height = contentView.frame.size.height
// Labels
usernameLabel.frame = CGRect(x: (width-(size*3))/2, y: height-880-(size/2), width: size*3, height: size)
// Buttons
profileButton.frame = CGRect(x: width-(size*7), y: height-850-size, width: size, height: size)
shareButton.frame = CGRect(x: width-size, y: height-850-size, width: size, height: size)
newClipButton.frame = CGRect(x: width-size-10, y: height-175-size, width: size/1.25, height: size/1.25)
}
override func prepareForReuse() {
super.prepareForReuse()
usernameLabel.text = nil
player?.pause()
player?.seek(to: CMTime.zero)
}
public func configure(with model: VideoModel) {
self.model = model
configureVideo()
// Labels
usernameLabel.text = model.username
}
private func configureVideo() {
guard let model = model else {
return
}
guard let url = URL(string: model.videoFileURL) else { return }
player = AVPlayer(url: url)
let playerView = AVPlayerLayer()
playerView.player = player
playerView.frame = contentView.bounds
playerView.videoGravity = .resizeAspect
videoContainer.layer.addSublayer(playerView)
player?.volume = 0
player?.play()
player?.actionAtItemEnd = .none
}
required init?(coder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}
Here is the view controller code:
import UIKit
struct VideoModel {
let username: String
let videoFileURL: String
}
class BetaClipsViewController: UIViewController, UICollectionViewDelegate {
private var collectionView: UICollectionView?
private var data = [VideoModel]()
/// Notification observer
private var observer: NSObjectProtocol?
/// All post models
private var allClips: [(clip: Clip, owner: String)] = []
private var viewModels = [[ClipFeedCellType]]()
override func viewDidLoad() {
super.viewDidLoad()
title = ""
// for _ in 0..<10 {
// let model = VideoModel(username: "#CJMJM",
// videoFileURL: "https://firebasestorage.googleapis.com:443/v0/b/globe-e8b7f.appspot.com/o/clipvideos%2F1637024382.mp4?alt=media&token=c12d0481-f834-4a17-8eee-30595bdf0e8b")
// data.append(model)
// }
let layout = UICollectionViewFlowLayout()
layout.scrollDirection = .horizontal
layout.itemSize = CGSize(width: view.frame.size.width,
height: view.frame.size.height)
layout.sectionInset = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)
layout.minimumInteritemSpacing = 0
layout.minimumLineSpacing = 0
collectionView = UICollectionView(frame: .zero, collectionViewLayout: layout)
collectionView?.register(ClipsCollectionViewCell.self,
forCellWithReuseIdentifier: ClipsCollectionViewCell.identifier)
collectionView?.isPagingEnabled = true
collectionView?.delegate = self
collectionView?.dataSource = self
view.addSubview(collectionView!)
fetchClips()
observer = NotificationCenter.default.addObserver(
forName: .didPostNotification,
object: nil,
queue: .main
) { [weak self] _ in
self?.viewModels.removeAll()
self?.fetchClips()
}
self.collectionView?.reloadData()
}
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
collectionView?.frame = view.bounds
}
private func fetchClips() {
guard let username = UserDefaults.standard.string(forKey: "username") else {
return
}
let userGroup = DispatchGroup()
userGroup.enter()
var allClips: [(clip: Clip, owner: String)] = []
DatabaseManager.shared.users(for: username) { usernames in
defer {
userGroup.leave()
}
let users = usernames + [username]
for current in users {
userGroup.enter()
DatabaseManager.shared.clips(for: current) { result in
DispatchQueue.main.async {
defer {
userGroup.leave()
}
switch result {
case .success(let clips):
allClips.append(contentsOf: clips.compactMap({
(clip: $0, owner: current)
}))
case .failure:
break
}
}
}
}
}
userGroup.notify(queue: .main) {
let group = DispatchGroup()
self.allClips = allClips
allClips.forEach { model in
group.enter()
self.createViewModel(
model: model.clip,
username: model.owner,
completion: { success in
defer {
group.leave()
}
if !success {
print("failed to create VM")
}
}
)
}
group.notify(queue: .main) {
self.collectionView?.reloadData()
}
}
}
}
extension BetaClipsViewController: UICollectionViewDataSource {
func numberOfSections(in collectionView: UICollectionView) -> Int {
return viewModels.count
}
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return viewModels[section].count
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cellType = viewModels[indexPath.section][indexPath.row]
switch cellType {
case .clip(let viewModel):
guard let cell = collectionView.dequeueReusableCell(withReuseIdentifier: ClipsCollectionViewCell.identifier,
for: indexPath)
as? ClipsCollectionViewCell else {
fatalError()
}
cell.delegate = self
cell.configure(with: viewModel)
return cell
}
}
}
extension BetaClipsViewController: ClipsCollectionViewCellDelegate {
func didTapProfile(with model: VideoModel) {
print("profile tapped")
let owner = model.username
DatabaseManager.shared.findUser(username: owner) { [weak self] user in
DispatchQueue.main.async {
guard let user = user else {
return
}
let vc = ProfileViewController(user: user)
self?.navigationController?.pushViewController(vc, animated: true)
}
}
}
func didTapShare(with model: VideoModel) {
print("profile share")
}
func didTapNewClip(with model: VideoModel) {
let vc = RecordViewController()
navigationController?.pushViewController(vc, animated: true)
}
}
extension BetaClipsViewController {
func createViewModel(
model: Clip,
username: String,
completion: #escaping (Bool) -> Void
) {
StorageManager.shared.profilePictureURL(for: username) { [weak self] profilePictureURL in
guard let clipURL = URL(string: model.clipUrlString),
let profilePhotoUrl = profilePictureURL else {
return
}
let clipData: [ClipFeedCellType] = [
.clip(viewModel: VideoModel(username: username,
videoFileURL: model.clipUrlString))
]
self?.viewModels.append(clipData)
completion(true)
}
}
}
I think everything is set up properly in the code so why do no cells show in the collectionView? The view controller shows up as completely blank besides the background color.