C# ClaimedBarcodeScanner events not firing in Windows 10 Build 19043.1645

Question

C# ClaimedBarcodeScanner events not firing in Windows 10 Build 19043.1645

Gaurang 1

Hello,

our company develops Kiosk Applications using Windows 10 IoT Enterprise LTSC.

We are developing a new stack using WinUI3 and Windows App SDK v1.0 for our application. Unfortunately, on our development machines which run Windows 10 Pro Build Version 19043.1645, the DataReceived and other Events are not fired at all! The same application when run on the Windows 10 IoT Enterprise LTSC machines (Build 1809) works flawlessly with the same Barcode Scanner (same configuration as well, in HID POS mode). There seems to be a bug here somewhere and we would like it to be fixed asap. as it affects us drastically.

More Information:

1.) The UWP Barcode Scanner example project (C#) has the same issues as well, so it is not dependent on our code.

2.) The UWP Barcode Scanner example project (C++) works without any issues, so the problem seems to be somewhere in the C# API.

Best Regards,
Gaurang Ingale

HelloGuest Solutions GmbH

Anonymous

2022-04-22T02:59:45.847+00:00

I have some questions here. Are you running the UWP sample on a normal windows 10 device or you are running it on a windows 10 IoT device? When you are using the C# sample, does the GetFirstBarcodeScannerAsync method return the correct barcode scanner?
Gaurang 1 Reputation point

2022-04-30T12:12:38.547+00:00

The UWP sample was run by me on a normal Windows 10 device (a Thinkpad Laptop). Yes, GetFirstBarcodeScannerAsync returns the correct barcode scanner and the claiming process goes through flawlessly as well. Just that there are no events being fired, like for example, DataReceived.
Anonymous

2022-05-03T03:08:51.773+00:00

@Gaurang That's interesting. Do you have other barcode scanner that could used for a test? Is this behavior related to specific barcode scanner?
Gaurang 1 Reputation point

2022-05-05T13:52:17.567+00:00

@Anonymous Yep, our company does use quite a few different barcode scanner models and those from different companies as well. This issue is not related to the Barcode Scanner at all. It is definitely something with either the C# API or the underlying Windows Service (Device Association Service). For more details about the issue, please check out my reply to @Limitless Technology answer.
Anonymous

2022-05-06T01:07:59.18+00:00

@Gaurang Could you please tell me what kinds of barcode scanners you've tested for this behavior? As I mentioned, we want to know whether this behavior happens to every barcode scanner on your side and we want to know the types of the barcode scanners that you are using.
Gaurang 1 Reputation point

2022-05-12T09:46:37.413+00:00

Newland NLS-FM30 and two other Honeywell scanners of which the model numbers I unfortunatley don't have at hand at this moment. All scanners were configured to use the HID POS mode which the Windows.Devices Namespace clearly supports.

As mentioned earlier, the C++ implementation of the BarcodeScanner UWP example from Microsoft worked perfectly no matter what. C# is where the issues are at, irrespective of the Windows Build Version.
Anonymous

2022-05-16T06:47:24.817+00:00

Thank you for sharing the information. I'll consult the team about this behavior via our internal channel. There might be some time delay.
Gaurang 1 Reputation point

2022-05-19T06:58:39.143+00:00

Thanks a lot!
Gaurang 1 Reputation point

2022-12-01T16:26:24.967+00:00

It has been a couple of months since your last response on this thread. Is there any news on this topic? The same problem still exists even in the newest Windows 11 Pro Builds which we use on our development machines.

1 answer

Your answer

Anonymous

2022-04-22T02:59:45.847+00:00

I have some questions here. Are you running the UWP sample on a normal windows 10 device or you are running it on a windows 10 IoT device? When you are using the C# sample, does the GetFirstBarcodeScannerAsync method return the correct barcode scanner?
Gaurang 1 Reputation point

2022-04-30T12:12:38.547+00:00

The UWP sample was run by me on a normal Windows 10 device (a Thinkpad Laptop). Yes, GetFirstBarcodeScannerAsync returns the correct barcode scanner and the claiming process goes through flawlessly as well. Just that there are no events being fired, like for example, DataReceived.
Anonymous

2022-05-03T03:08:51.773+00:00

@Gaurang That's interesting. Do you have other barcode scanner that could used for a test? Is this behavior related to specific barcode scanner?
Gaurang 1 Reputation point

2022-05-05T13:52:17.567+00:00

@Anonymous Yep, our company does use quite a few different barcode scanner models and those from different companies as well. This issue is not related to the Barcode Scanner at all. It is definitely something with either the C# API or the underlying Windows Service (Device Association Service). For more details about the issue, please check out my reply to @Limitless Technology answer.
Anonymous

2022-05-06T01:07:59.18+00:00

@Gaurang Could you please tell me what kinds of barcode scanners you've tested for this behavior? As I mentioned, we want to know whether this behavior happens to every barcode scanner on your side and we want to know the types of the barcode scanners that you are using.
Gaurang 1 Reputation point

2022-05-12T09:46:37.413+00:00

Newland NLS-FM30 and two other Honeywell scanners of which the model numbers I unfortunatley don't have at hand at this moment. All scanners were configured to use the HID POS mode which the Windows.Devices Namespace clearly supports.

As mentioned earlier, the C++ implementation of the BarcodeScanner UWP example from Microsoft worked perfectly no matter what. C# is where the issues are at, irrespective of the Windows Build Version.
Anonymous

2022-05-16T06:47:24.817+00:00

Thank you for sharing the information. I'll consult the team about this behavior via our internal channel. There might be some time delay.
Gaurang 1 Reputation point

2022-05-19T06:58:39.143+00:00

Thanks a lot!
Gaurang 1 Reputation point

2022-12-01T16:26:24.967+00:00

It has been a couple of months since your last response on this thread. Is there any news on this topic? The same problem still exists even in the newest Windows 11 Pro Builds which we use on our development machines.

Answer 1

Limitless Technology 39,931

Hi there,

As it is evident that the code is not firing only on Windows 10 Pro Build Version 19043.1645 it as advised to raise a ticket or submit the feedback to the Windows development team who would review and release subsequent patches to sort this out.

Also check the Event that is raised when the ClaimedBarcodeScanner is closed. When an application is suspended, all ClaimedBarcodeScanner objects are closed. This event can be useful to determine when barcode scanner connections need to be re-established.

Below threads discusses the same issue and you can look into it for some insights.
UWP Barcodescanner DataReceived Event not firing https://social.msdn.microsoft.com/Forums/en-US/80f7536e-a2ac-4f07-9b56-8cf7a4932e6e/uwp-barcodescanner-datareceived-event-not-firing?forum=wpdevelop

--If the reply is helpful, please Upvote and Accept it as an answer–

Gaurang 1 Reputation point

2022-04-30T12:20:03.323+00:00

Hello @Limitless Technology ,

thanks for your input on this topic. To circumvent this problem altogether, as it was hindering our development progress, I upgraded to Windows 11 Build 22000.613.

Now, I am able to get the events to trigger, but as soon as the application is closed (the app we are developing) and reopened, the same problem as on the previous Build Version occurs again. And this, inspite of resetting all event handlers as well as calling the Dispose method on both the BarcodeScanner and the ClaimedBarcodeScanner objects before the application is closed, to make sure that the device is free to be used by any other currently active or future process. So no, this issue is not Build Version specific.

By the way, on Windows 11 Build 22000.613, I can make the events trigger again after closing and reopening my application by restarting the Windows Device Association Service in services.msc, so the bug could be either in this service or the underlying HID Driver.

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C# ClaimedBarcodeScanner events not firing in Windows 10 Build 19043.1645

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