Scanner not working sometimes

[VictorKochetkov]

I've faced with some strange scanner behavior on Android.

On some devices scanner not working (not scanning) at first page opening. I have to close page and open it again. After that scanner works correctly.

May be some "internal" things not ready on first try?
For example there https://github.com/JimmyPun610/BarcodeScanner.XF/blob/dd8c0d099b4c155a9aefd2accb92afe28affcf51/GoogleVisionBarCodeScanner/Android/Renderer/CameraViewRenderer.cs#L84

[vladPanasiuk]

I have the same problem. In Debug mode, this is rare, but in Release it occurs every time

[JimmyPun610]

maybe related to #105

[istanko]

Hi,

In my case this is happening when proxy?.Close(); in SafeCloseImageProxy method in Android CameraViewRenderer.cs line 410 raise the ArgumentException.

private void SafeCloseImageProxy(IImageProxy proxy)
{
	try
	{
		proxy?.Close();
   	}
   	catch (ObjectDisposedException) { }
   	catch (ArgumentException)
   	{
      	//Ignore argument exception, it will be thrown if BarcodeAnalyzer get disposed during 		processing
    	}
}

System.ArgumentException: Handle must be valid.
Parameter name: instance
at Java.Interop.JniEnvironment+InstanceMethods.CallVoidMethod (Java.Interop.JniObjectReference instance, Java.Interop.JniMethodInfo method) [0x00009] in /Users/runner/work/1/s/xamarin-android/external/Java.Interop/src/Java.Interop/Java.Interop/JniEnvironment.g.cs:11853
at Android.Runtime.JNIEnv.CallVoidMethod (System.IntPtr jobject, System.IntPtr jmethod) [0x00000] in /Users/runner/work/1/s/xamarin-android/src/Mono.Android/Android.Runtime/JNIEnv.g.cs:258
at AndroidX.Camera.Core.IImageProxyInvoker.Close () [0x0002d] in D:\a\1\s\generated\androidx.camera.camera-core\obj\Release\monoandroid9.0\generated\src\AndroidX.Camera.Core.IImageProxy.cs:467
at BarcodeScanner.Mobile.XamarinForms.Renderer.CameraViewRenderer+BarcodeAnalyzer.SafeCloseImageProxy (AndroidX.Camera.Core.IImageProxy proxy, BarcodeScanner.Mobile.XamarinForms.Renderer.CameraViewRenderer _renderer) [0x00002]

After this exception scanning stops.

I've managed to add quick and dirty workaround with calling:

try
{
    proxy?.Close();
}
catch (ObjectDisposedException) { }
catch (ArgumentException)
{
    //Ignore argument exception, it will be thrown if BarcodeAnalyzer get disposed during processing
    Device.BeginInvokeOnMainThread(() =>
    {
        _renderer.CameraCallback();
    });
}

[mantasdaskev]

Hi, wanted to now if there is any progress made with this issue?

[MridulMalviya]

I am also facing same issue for Android Kyocera dual force pro device.
Sometimes it is working if we move application from background state to foreground state.

[Serverator]

I have the same issue, using 6.3.0.29 in MAUI
In debug it works all the time, but when I switch to release there is like 1/5 chance that scanner won't send any OnDetected events when opened.