[BUG] Problems with Some CameraView StopVideoRecording on IOS

[neji94]

Is there an existing issue for this?

• I have searched the existing issues

Did you read the "Reporting a bug" section on Contributing file?

• I have read the "Reporting a bug" section on Contributing file: https://github.com/CommunityToolkit/Maui/blob/main/CONTRIBUTING.md#reporting-a-bug

Current Behavior

HI i have an Problem what appears in some apps and only after recordiong more the around 6 secounds. Whenn it happens the StopVideoRecording function not ends ant it seams so that the TaskCompletionSource used in cambination with AVCaptureMovieFileOutputRecordingDelegate not been set to compleat. But Why and why i cannot recreate it in every app? hasy anywone an idear?

my Used call to start and stop the recording is the following:
` ToogleRecord = new AsyncRelayCommand(async () => {
try
{
if (TakeVideo)
{
Console.WriteLine($"Recording Is video: IsRunning: {VideoIsRunning}");
if (!VideoIsRunning)
{

              if (movieStream != null)
              {
                  try
                  {
                      await movieStream.DisposeAsync();
                  }
                  catch { }
                  movieStream = null;
              }

              if (File.Exists(Path.Combine(FileSystem.Current.AppDataDirectory, "tem_recording.mp4")))
                  File.Delete(Path.Combine(FileSystem.Current.AppDataDirectory, "tem_recording.mp4"));

              movieStream = new FileStream(Path.Combine(FileSystem.Current.AppDataDirectory, "tem_recording.mp4"), FileMode.Create, FileAccess.ReadWrite, FileShare.Read, 4096, true);
              movieStream.Position = 0;
     

              await cameraView.StartVideoRecording(movieStream, CancellationToken.None);
              VideoIsRunning = true;
              Console.WriteLine("Recording Stared");
          }
          else
          {
              Console.WriteLine("Recording stopeding");
              //cameraView.StopCameraPreview();
              await cameraView.StopVideoRecording(CancellationToken.None);
          
              Console.WriteLine("Recording stoped 1");
              await movieStream.DisposeAsync();
              Console.WriteLine("Recording stoped 2");
              movieStream = null;
              VideoIsRunning = false;
              Console.WriteLine("Recording stoped 3");
              returnFunc.Invoke(new List<MediaFile>() { new TakenMediaFile(TakeVideo, new FileStream(Path.Combine(FileSystem.Current.AppDataDirectory, "tem_recording.mp4"), FileMode.Open, FileAccess.Read, FileShare.Read)) });
              Console.WriteLine("Recording stoped");

          }
      }
      else
      {

          Console.WriteLine($"Error: Files Selected count {SelectedFiles?.Count()}");

          var captureImageCTS = new CancellationTokenSource(TimeSpan.FromSeconds(3));
          var photo = await cameraView.CaptureImage(captureImageCTS.Token);
          returnFunc.Invoke(new List<MediaFile>() { new TakenMediaFile(TakeVideo, photo) });
      }
      await OnPropertyChangedAsync(null);
  }
  catch (Exception ex) {
      Console.WriteLine($"Recording Error: {ex}");
  
  }

});`

The CameraView is opend in an Popup.

Expected Behavior

Exiting the function and an filled video stream/file

Steps To Reproduce

Not known. It seams to happen after at least 6 sec. of recording

Link to public reproduction project repository

Could not Create one

Environment

- .NET MAUI CommunityToolkit: 13.0.0
- .NET MAUI CommunityToolkit Camera: 6.0.0
- OS: Ios > 16.0
- .NET MAUI: 10.0.50

Anything else?

No response

[neji94]

https://github.com/neji94/VideoBugDemo
Here's an example. It seems to be a problem that the AVCaptureMovieFileOutputRecordingDelegate could not be executed or was ignored because of a heavy UI load. In this demo app, I recreated it by using a timer that changes a label every 1/10 of a second. In my original app, it seems to have something to do with UI calculations for positioning and rotations. That's all I can give you as information for now.

[neji94]

I now have a litle bit mor information: the ui load causing this problem comes in my original App from an simple SKIA/Lottie animation running in the background. So it seams evry hevyer ui Calculation will cause this.

[ne0rrmatrix]

Can you test using this PR: #3157

[neji94]

The PR does not fix this problem. Sorry.

[neji94]

I think I found the solution for this to prevent the loss of the AVCaptureFileOutputRecordingDelegate. It needs to have a strong reference and not be injected directly into the videoOutput.StartRecordingToOutputFile function. I have tried it with my demo and original app without changes, and now it works without any problems. Is there somebody who could look into this with some more experience in iOS to check if my changes wouldn't have any impact or if there are any other changes to be made? Here's the file I currently added into my demo repo: https://github.com/neji94/VideoBugDemo/blob/master/fix_CameraManager.macios.cs