I am trying to connect my phone to an HC06 as part of a robotics project but when I try to connect, it fails around 75% of the time and often fails to send the full message. Here is the relevant code:
public class send extends AsyncTask<Void, Void, Void> {
BluetoothAdapter BA = BluetoothAdapter.getDefaultAdapter();
BluetoothSocket BS;
boolean Success = false;
@Override
protected void onPreExecute(){
Toast.makeText(getApplicationContext(), "Connecting", Toast.LENGTH_SHORT).show();
}
@Override
protected Void doInBackground(Void... voids) {
try {
BluetoothDevice wantedDevice = BA.getRemoteDevice("20:16:07:27:71:97");
UUID myUUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
BS = wantedDevice.createInsecureRfcommSocketToServiceRecord(myUUID);
BA.cancelDiscovery();
BS.connect();
Success = true;
} catch (IOException e) {
e.printStackTrace();
Success = false;
}
return null;
}
@Override
protected void onPostExecute(Void result){
OutputStream mmOutStream = null;
if(Success) {
try {
mmOutStream = BS.getOutputStream();
} catch (IOException e) {
e.printStackTrace();
}
for (int i = 0; i < Savefile.size(); i++) {
String message = Savefile.get(i);
if (!Objects.equals(message, null) && mmOutStream != null && !Objects.equals(message, " ") && !Objects.equals(message, "x")) {
try {
mmOutStream.write(message.getBytes());
} catch (IOException e) {
e.printStackTrace();
}
}
}
if (mmOutStream != null) {
try {
mmOutStream.write("e".getBytes());
} catch (IOException e) {
e.printStackTrace();
}
}
Toast.makeText(getApplicationContext(), "Sent", Toast.LENGTH_SHORT).show();
}
else {
Toast.makeText(getApplicationContext(), "Connection Failed", Toast.LENGTH_SHORT).show();
}
if (mmOutStream != null) {
try {
mmOutStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if(BS != null){
try {
BS.close();
} catch (IOException e) {
e.printStackTrace();
}
}
final ImageButton sendButton = (ImageButton) findViewById(R.id.sendbutton);
sendButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if(BA != null) {
sendButton.setOnClickListener(null);
send a = new send();
a.execute();
}
else{
Toast.makeText(getApplicationContext(), "Bluetooth is off", Toast.LENGTH_SHORT).show();
}
}
});
}
}
It is mostly based on http://www.instructables.com/id/Android-Bluetooth-Control-LED-Part-2/?ALLSTEPS
The main question is am I connecting in the right way for a short-term connection down which I am sending single bytes of data?
EDIT: Here is the error it throws
W/System.err: java.io.IOException: read failed, socket might closed or timeout, read ret: -1
W/System.err: at android.bluetooth.BluetoothSocket.readAll(BluetoothSocket.java:508)
W/System.err: at android.bluetooth.BluetoothSocket.readInt(BluetoothSocket.java:519)
W/System.err: at android.bluetooth.BluetoothSocket.connect(BluetoothSocket.java:323)
W/System.err: at com.croweinc.iconturtle.MainActivity$send.doInBackground(MainActivity.java:246)
W/System.err: at com.croweinc.iconturtle.MainActivity$send.doInBackground(MainActivity.java:232)
W/System.err: at android.os.AsyncTask$2.call(AsyncTask.java:288)
W/System.err: at java.util.concurrent.FutureTask.run(FutureTask.java:237)
W/System.err: at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
W/System.err: at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
W/System.err: at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
W/System.err: at java.lang.Thread.run(Thread.java:848)
