How do I get an app to read data from a USB barcode reader if the usbManager can't even detect that its there.
On Thursday, September 19, 2013 3:55:19 PM UTC-4, eli wrote: > <http://stackoverflow.com/questions/18900666/android-usb-problems#> > ** > > I have a tablet, an OTG cable and a barcode reader. I know this works > because when I start the Google app I can scan barcodes and see them on the > screen. > > I created a very simple application that starts the USB manager and checks > how many devices are attached. > > When I have a memory flash stick in the OTG cable the program shows 1. > (correct) > > When I have a mouse in the OTG cable it shows 0. (why) > > Interesting observation. When I connect the mouse to the OTG cable it > works fine. I use it to click on the button to ask the usbManager how many > devices are attached and the response is 0. > > When I attach a barcode reader to the OTG cable, the application goes > through onDestroy() and then shows 0. (Why does this happen) > > Basics of my program developed using Eclipse: > > In onCreate() I have: > > usbManager = (UsbManager)getSystemService(Context.USB_SERVICE); > > > > In onClick() I have (there is a button on the screen): > > Map<String, UsbDevice> usbDeviceList = > sbManager.getDeviceList();Toast.makeText(this, String.format("Number of > devices = %d", usbDeviceList.size()), Toast.LENGTH_SHORT).show(); > > -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en --- You received this message because you are subscribed to the Google Groups "Android Developers" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/groups/opt_out.
