Xamarin Android升级至.NET 8后ZXing.Net.Mobile扫码功能异常求助

修复ZXing.Net.Mobile适配.NET 8的方法 #

• 升级至预发布版本：ZXing.Net.Mobile的正式版可能未完全适配.NET 8，可尝试安装NuGet上的预发行包，通过命令行执行：

  Install-Package ZXing.Net.Mobile.Android -Pre
  

• 调整权限与初始化逻辑：Android 13+对相机权限要求更严格，需确保动态申请权限后再初始化扫码器：

  private const int RequestCameraPermission = 1;
  
  protected override void OnCreate(Bundle savedInstanceState)
  {
      base.OnCreate(savedInstanceState);
      CheckCameraPermissionAndInitializeScanner();
  }
  
  private void CheckCameraPermissionAndInitializeScanner()
  {
      if (ContextCompat.CheckSelfPermission(this, Manifest.Permission.Camera) != Permission.Granted)
      {
          ActivityCompat.RequestPermissions(this, new[] { Manifest.Permission.Camera }, RequestCameraPermission);
      }
      else
      {
          MobileBarcodeScanner.Initialize(Application);
      }
  }
  
  public override void OnRequestPermissionsResult(int requestCode, string[] permissions, Permission[] grantResults)
  {
      base.OnRequestPermissionsResult(requestCode, permissions, grantResults);
      if (requestCode == RequestCameraPermission && grantResults.Any(r => r == Permission.Granted))
      {
          MobileBarcodeScanner.Initialize(Application);
      }
  }
  

• 替换控件初始化方式：若使用ZXingScannerView，尝试通过代码实例化而非AXML布局绑定，避免兼容性问题：

  var scannerView = new ZXingScannerView(this);
  scannerView.OnScanResult += (sender, result) => {
      // 处理扫码结果
  };
  SetContentView(scannerView);
  

兼容.NET 8 Android的二维码扫描替代库 #

• ZXing.Net核心库：放弃ZXing.Net.Mobile的封装层，直接使用ZXing.Net核心库自行实现相机预览与解码，兼容性更强，灵活性更高。只需安装ZXing.Net包，结合Android相机API获取帧数据后调用解码方法即可。
• Google ML Kit条码扫描：官方提供的工具，对.NET 8 Android支持完善，性能稳定，支持离线扫码。安装Xamarin.Google.MLKit.BarcodeScanning包后，可快速集成：

  private BarcodeScanner _scanner;
  
  protected override void OnCreate(Bundle savedInstanceState)
  {
      base.OnCreate(savedInstanceState);
      _scanner = BarcodeScanning.GetClient(
          new BarcodeScannerOptions.Builder().SetBarcodeFormats(Barcode.Format.QrCode).Build()
      );
      // 结合相机预览获取图像帧，传入_scanner.ProcessImageAsync()解码
  }
  

• BarcodeScanner.Mobile：专为.NET Android/MAUI设计的轻量库，API简洁开箱即用。安装BarcodeScanner.Mobile包后，一行代码即可发起扫码：

  var scanner = new BarcodeScanner();
  var result = await scanner.ScanAsync(this);
  if (result != null)
  {
      string qrContent = result.Text;
  }
  

内容的提问来源于stack exchange，提问作者Niroshan K