My goal is very basic. I am trying to transmit a String from my android device to my Mac running OSX 10.9 via bluetooth. On my Mac I am using the lightblue python library to do the connections. I am pretty sure that the issue is raised by a cast-like exception between what methods are expecting (more detail below). I am relatively new to this type of networking. This is ultimately going to become a rough proof of concept. Any advice would work as well.
Thanks!
Android Code (Sending String):
public class Main extends Activity {
private OutputStream outputStream;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
try {
init();
write("Test");
} catch (IOException e) {
e.printStackTrace();
}
}
private void init() throws IOException {
BluetoothAdapter blueAdapter = BluetoothAdapter.getDefaultAdapter();
if (blueAdapter != null) {
if (blueAdapter.isEnabled()) {
Set<BluetoothDevice> bondedDevices = blueAdapter.getBondedDevices();
if(bondedDevices.size() > 0){
BluetoothDevice device = (BluetoothDevice) bondedDevices.toArray()[0];
ParcelUuid[] uuids = device.getUuids();
BluetoothSocket socket = device.createRfcommSocketToServiceRecord(uuids[0].getUuid());
socket.connect();
outputStream = socket.getOutputStream();
}
Log.e("error", "No appropriate paired devices.");
}else{
Log.e("error", "Bluetooth is disabled.");
}
}
}
public void write(String s) throws IOException {
outputStream.write(s.getBytes());
}
public void run() {
final int BUFFER_SIZE = 1024;
byte[] buffer = new byte[BUFFER_SIZE];
int bytes = 0;
while (true) {
try {
bytes = inStream.read(buffer, bytes, BUFFER_SIZE - bytes);
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
Adapted from: Android sample bluetooth code to send a simple string via bluetooth
Python LightBlue Example Code (Receiving String):
import lightblue
# create and set up server socket
sock = lightblue.socket()
sock.bind(("", 0)) # bind to 0 to bind to a dynamically assigned channel
sock.listen(1)
lightblue.advertise("EchoService", sock, lightblue.RFCOMM)
print "Advertised and listening on channel %d..." % sock.getsockname()[1]
conn, addr = sock.accept()
print "Connected by", addr
data = conn.recv(1024) #CRASHES HERE
print "Echoing received data:", data
# sometimes the data isn't sent if the connection is closed immediately after
# the call to send(), so wait a second
import time
time.sleep(1)
conn.close()
sock.close()
Error in console:
python test.py
Advertised and listening on channel 1...
Connected by ('78:52:1A:69:B2:6D', 1)
Traceback (most recent call last):
File "test.py", line 16, in <module>
data = conn.recv(1024)
File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/lightblue/_bluetoothsockets.py", line 470, in recv
return self.__incomingdata.read(bufsize)
File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/lightblue/_bluetoothsockets.py", line 150, in read
self._build_str()
File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/lightblue/_bluetoothsockets.py", line 135, in _build_str
new_string = "".join(self.l_buffer)
TypeError: sequence item 0: expected string, memoryview found
The last line is where I am pretty sure I am messing up. It is expecting a string, but I am pretty sure I am not sending a memoryview (as far as I am aware).
