Gradle / Android-studio based project.
Import projects ExternalNFCCore, NFCToolsForJavaAndroid, ExternalNFCAPI and ndeftools into your workspace.
Then add all projects except ndeftools as library projects to your application.
Launch the service BackgroundUsbService. If started without a connected reader, the service remains alive and looks for a reader. If there is no USB permission granted already, the app will ask for such a permission whenever a reader is connected.
For some Android devices the reader permission is not saved via the request usb permission operation in the service. To stop the 'permission box' from reappearing, add an activity which triggers on the right filter
<intent-filter>
<action android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED" />
</intent-filter>
<meta-data android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED" android:resource="@xml/accessory_filter" />
with accessory_filter
<resources>
<usb-device vendor-id="1839" />
</resources>
where 1839 is ACS.
The service has some configuration options, loaded from shared preferences. These are listed in the top of the service class.
There is a partial implementation of bluetooth reader support, this is currently not working acceptable because the devices are put in a bad state when setting the 'sleep mode'. The devices must then be reset using a obscure tool which restores its state - see the docs folder. Note: The tool can also be using via a Windows virtual machine.