Android USB manager only sees devices after they are re-attached -


the function usbmanager.getdevicelist() should return list of attached devices. however, list empty upon startup of application until attached usb devices first physically removed , re-attached. after this, function correctly returns list of connected devices.

function use call it:

public static map<string, usbdevice> getavailabledevices(context context) {      usbmanager usbmanager = (usbmanager) context.getsystemservice(context.usb_service);     map<string, usbdevice> availableusbdevices = new hashmap<string, usbdevice>();      availableusbdevices = usbmanager.getdevicelist();      return availableusbdevices; }

the documentation of function usbmanager.getdevicelist() says gives remoteexception (which does) if no devices attached, or if usb host mode inactive or unsupported. don't means though since devices attached , usb host supported. (since works fine after devices re-attached)

edit: on closer inspection using debugger problem lies in function mservice.getdevicelist(bundle) within usbmanager.getdevicelist(). if re-attach usb devices before mservice.getdevicelist(bundle) gets called devices detected appropriately. must have system configuration..

any idea what's up?

thanks in advance


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