SwiftUI: Fetch Video from the Photo Album

VideoPlayerView.swift

import AVKit
import PhotosUI
import SwiftUI

struct VideoTransferable: Transferable {
  let url: URL
  
  static var transferRepresentation: some TransferRepresentation {
    FileRepresentation(contentType: .movie) { exporting in
      return SentTransferredFile(exporting.url)
    } importing: { received in
      let origin = received.file
      let filename = origin.lastPathComponent
      let copied = URL.documentsDirectory.appendingPathComponent(filename)
      let filePath = copied.path()
      
      if FileManager.default.fileExists(atPath: filePath) {
        try FileManager.default.removeItem(atPath: filePath)
      }
      
      try FileManager.default.copyItem(at: origin, to: copied)
      return VideoTransferable(url: copied)
    }
  }
}

struct VideoPlayerView: View {
  @State private var player = AVPlayer()
  @State private var photosPickerItem: PhotosPickerItem?
  @State private var errorMessage: String?
  @State private var showAlert: Bool = false
  
  var body: some View {
    /// 1. UI
    VStack {
      VideoPlayer(player: player)
      
      PhotosPicker(
        "Select a video",
        selection: $photosPickerItem,
        matching: .videos
      )
    }
    /// 3. Observing
    .onChange(of: photosPickerItem) { oldValue, newValue in
      if let newValue {
        Task {
          do {
            if let url = try await loadVideo(newValue) {
              let playerItem = AVPlayerItem(url: url)
              player.replaceCurrentItem(with: playerItem)
            }
          } catch {
            errorMessage = error.localizedDescription
            showAlert.toggle()
          }
        }
      }
    }
    /// 4. Alert
    .alert(errorMessage ?? "", isPresented: $showAlert, actions: {})
  }
  
  /// 2. Load Video
  private func loadVideo(_ item: PhotosPickerItem) async throws -> URL? {
    guard let video = try await item.loadTransferable(type: VideoTransferable.self) else {
      return nil
    }
    return video.url
  }
}