I ran into this issue today when debugging on Android, so posting what took an hour to figure out 🙂 This is for when you’re getting a null reference exception when attempting to scan. I was following the instructions here, and then, well, it wouldn’t work 🙂
Rather than using the Dependency Resolver, you’ll need to pass in the Application Context from Android. So, in the App, create a static reference to the IQrCodeScanner,, as follows:
public partial class App : Application
{
public static IQrCodeScanningService QrCodeScanningService;
Then, populate that static instance from the Android app, as follows:
App.QrCodeScanningService = new QrCodeScanningService(this); global::Xamarin.Forms.Forms.Init(this, bundle); LoadApplication(new App());
Obviously you’ll also need a matching constructor, like so:
public class QrCodeScanningService : IQrCodeScanningService
{
private readonly Context _context;
public QrCodeScanningService(Context context)
{
_context = context;
}
This solved the problem like magic for me. I hope it helps you, too!
P.S. Make sure you have the CAMERA permission. I’ve also read you may also need the FLASHLIGHT permission, although I’m not entirely sure that’s required.
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