Removed tests, added AndroidX explicitly and added callback interface

app/src/main/java/com/example/nrftest/DecaManager.java

@@ -7,6 +7,7 @@ import android.bluetooth.BluetoothGattService;
 import android.content.Context;
 import android.util.Log;
 
+import java.io.ByteArrayOutputStream;
 import java.util.UUID;
 
 import androidx.annotation.NonNull;
@@ -87,6 +88,14 @@ public class DecaManager extends BleManager<DecaManagerCallbacks> {
         @Override
         public void onDataReceived(@NonNull BluetoothDevice device, @NonNull Data data) {
             Log.d(TAG, "onDataReceived: length=" + data.size() + " data=" + data);
+
+            ByteArrayOutputStream stream = new ByteArrayOutputStream();
+
+            for (int i = 0; i < data.size(); i++) {
+                stream.write(data.getByte(i));
+            }
+
+            mCallbacks.onTagLocationData(stream.toByteArray());
         }
 
         @Override