BarcodeScanner stops detect after some time

[MateusMiotto]

Describe the bug
After an indeterminate amount of time, Barcode detection simply does not happen. I didn't get anything different in the log, just the usual:
[UseCaseAttachState] Active and attached use case: [androidx.camera.core.Preview-d8c6eaeb-2536-4024-99fa-912bef01aeb1128811641, androidx.camera.core.ImageAnalysis-a1ea55de-92b1-473a-95d1-b0a97f9ffe90219505695] for camera: 1
[CaptureSession] Attempting to submit CaptureRequest after setting
[CaptureSession] Issuing request for session.

In my tests, after approximately 1~2 hours the detection simply stopped.

To Reproduce
I uploaded a project based on the library example, with MVVM sample (even in code behind the bug persists)

Steps to reproduce the behavior:

1. Clone and restore packages of https://github.com/MateusMiotto/BarcodeScanner
2. Run the project
3. Wait a certain amount of time without making the detection, (for me 1~2 hours without taking any reading) and the detection simply stops happening and without any error in logs

Expected behavior
The component, even with the camera open performing the detection, even without detecting any barcode for hours, does not stop scanning

Smartphone (please complete the following information):

• Device: [Note 8 pro, Samsumg A54, Galaxy Tab A9+]
• OS: [Android 14 and Android 11]
• Version [Maui v8.0.40]

[ManuLin]

I am facing the same issue Mateus mentioned. After a random amount of time, the scanner seems to stop scanning without an exception being thrown. Any hints are highly appreciated. We are using the "BarcodeScanner.Mobile.Maui" package in version 8.0 and can observe the issue on Android devices as well.

[MateusMiotto]

Any updates about this issue?

[DannyGit]

Hi,
we had the same issue in our NET8 Maui app and solved it by adding a Timer to the code-behind that toggles the 'IsScanning' Property of the CameraView, effectively re-starting the scan process every few seconds

protected override void OnNavigatedTo(NavigatedToEventArgs args)
{
       ..        
      StartScanning();
}

  /// <summary>
  /// The scan process will be active for four seconds and then get reset by a timer.
  /// The timer will disable the scan process for a short period and then re-enable it for another four seconds and so on.
  /// workaround for: https://github.com/JimmyPun610/BarcodeScanner.Mobile/issues/243
  /// </summary>
  private void StartScanning()
  {
      this._viewModel.IsScanning = true;
      
      // Create a timer and set a two second interval.
      scannerTimer = new System.Timers.Timer();
      scannerTimer.Interval = 4000;

      // Hook up the Elapsed event for the timer. 
      scannerTimer.Elapsed += ToggleIsScanning;

      // Have the timer fire repeated events (true is the default)
      scannerTimer.AutoReset = true;

      // Start the timer
      scannerTimer.Enabled = true;
  }

  // disable scanner and after short delay, re-enable scanning again to re-init scan process
  private async void ToggleIsScanning(object sender, ElapsedEventArgs e)
  {
      this._viewModel.IsScanning = false;
      await Task.Delay(250);
      this._viewModel.IsScanning = true;
  }

  protected override void OnNavigatedFrom(NavigatedFromEventArgs args)
  {
      ...        
      scannerTimer.Enabled = false;
      scannerTimer.Elapsed -= ToggleIsScanning;
      scannerTimer.Dispose();
  }