I’m showing the complete code to copy and paste:

import SwiftUI
import PhotosUI
import AVKit


struct VidPlay: View {
    
    @State private var selectedItem: PhotosPickerItem? = nil
    @State var videoURL: URL? = nil
    @State var videoHeight: CGFloat = 160
    @State private var player: AVPlayer = AVPlayer()
    
    var body: some View {
        
        VStack(spacing: 20){
            
            PhotosPicker(selection: $selectedItem, matching: .videos){
                Image(systemName: "camera.fill")
                    .resizable()
                    .aspectRatio(contentMode: .fit)
                    .frame(height: 20)
                    .foregroundColor(Color.white)
                    .padding(2)

            }
            .task(id: selectedItem) {

                if(selectedItem != nil){
                    videoURL = nil

                    do {
                   
                       if let data = try await selectedItem?.loadTransferable(type: Data.self) {
                           
                           let bytes = Double(data.count)
                           let megabytes = bytes / (1024 * 1024)
                           
                           if (megabytes > 64) {
                               print("too big")
                           } else {

                               let tempFile = TemporaryMediaFile(withData: data)
                               
                               let asset = tempFile.avAsset
                               
                               let size = try await asset?.load(.tracks).first?.load(.naturalSize)
                               
                               if let duration = try? await asset!.load(.duration){
                                   let durationTime = CMTimeGetSeconds(duration)
                                   
                                   print(durationTime)
               
                                   if(durationTime < 3 || durationTime > 300){
                                       print("too short or too long")
                                   }else{
                                       videoHeight = 160 * (size!.height / size!.width)
                                       print(videoHeight)
                                       videoURL = tempFile.url
                                       print("video should play")
                                   }
                                   
                                   //tempFile.deleteFile()
                               }else{
                                   print("picking failed 2")
                               }
                           }
                       } else {
                           print("picking failed")
                       }
                   
                   } catch {
                       print(error)
                   }
                }

            }
            

            ZStack{
                if(videoURL != nil){
                    VideoPlayer(player: player)
                        .frame(width: 160, height: self.$videoHeight.wrappedValue)
                }
            }
            .onChange(of: videoURL) { _ in
                
                if(videoURL != nil){
                      
                    //player = nil
                    player = AVPlayer(url: videoURL!)
                    
                    DispatchQueue.main.asyncAfter(deadline: .now() + 0.5) {
                        player.play()
                    }
                }else{
                    player.pause()
                }
            }
            .frame(width: 240, height: 240)
            .background(Color.blue)

        }
    }
}


class TemporaryMediaFile {
    var url: URL?

    init(withData: Data) {
        let directory = FileManager.default.temporaryDirectory
        //let fileName = "(NSUUID().uuidString).mp4"
        let fileName = "temp.mp4"
        let url = directory.appendingPathComponent(fileName)
        do {
            try withData.write(to: url)
            self.url = url
        } catch {
            print("Error creating temporary file: (error)")
        }
    }

    public var avAsset: AVAsset? {
        if let url = self.url {
            return AVAsset(url: url)
        }

        return nil
    }

    public func deleteFile() {
        if let url = self.url {
            do {
                try FileManager.default.removeItem(at: url)
                self.url = nil
            } catch {
                print("Error deleting temporary file: (error)")
            }
        }
    }

    deinit {
        self.deleteFile()
    }
}

The durationTime and videoHeight are correct and “video should play” gets printed out, but the video isn’t playing. How to fix this?