I can not detect the USB device with Android USBManager -

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i trying use usbmanager of android, not find device connected usb. testing on emulator android, connected 1 card reader , want control reading of data, app can not read if there device connected usb port.

anyone had problem?

        usbmanager musbmanager = (usbmanager)getsystemservice(context.usbservice);          int countdevice = musbmanager.devicelist.count;          devicelist = musbmanager.devicelist;

does card reader work computer? perhaps driver needs installed first?

on other hand, have listed intent usb device manager:

<intent-filter>     <action android:name="android.hardware.usb.action.usb_device_attached" /> </intent-filter>

it helpful if posted error message get.


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