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Android Bluetoothsocket

Bluetoothyhteyden muodostaminen koitui projektin haastavimmaksi osuudeksi. Eri Android-versiot ja puhelimet toimivat eri tavoin kun muodostetaan laiteyhteyttä. Lisäksi käytettävä Bluetoothrauta ja Android eivät tykkää toisistaan (http://stackoverflow.com/questions/9052460/with-just-one-particular-bluetooth-spp-module-createrfcommsockettoservicerecor).

Ratkaisuna ongelmaan ohjelmassa käyttäjä voi valita mitä yhdistystapaa käytetään. Jos laiteyhteyksiä ei saa muodostettua, käyttäjä voi vaihtaa yhdistystapaa. Keräsin kaikki löytämäni bluetoothyhdistystavat, joilla jokaiseen testipuhelimeen löytyi oikeat asetukset.
/**
  * Luo socketin laitteeseen. Huom! yhdistämisessä paljon eroja eri
  * laitteiden välillä. Katso API-levelit ja android versioiden vastaavuudet
  * Androidin nettisivuilta. 

  * 

  * Yhdistystapaa voi muuttaa asetuksista. Oletuksena on neljä erilaista tapaa. Kts. 
  * @param device
  * 
  * @throws IOException
  */

 private BluetoothSocket createBluetoothSocket(BluetoothDevice device)
   throws IOException {
  try {
   final Method m;
   BluetoothDevice hxm;
   Log.i(BT_TAG, "Connection "+ MainActivity.CONNECTION_METHOD);
   switch (MainActivity.CONNECTION_METHOD) {
   case RFCOMMSECURE:
    return device.createRfcommSocketToServiceRecord(REMOTE_UUID);    
   case REFLECTION_RFCOMM:
    m = device.getClass().getMethod(
      "createRfcommSocketToServiceRecord",
      new Class[] { UUID.class });
    Log.i(BT_TAG, "createInsecure");
    return (BluetoothSocket) m.invoke(device, REMOTE_UUID);
   case REFLECTION_NOUUID:
    hxm = BluetoothAdapter.getDefaultAdapter().getRemoteDevice(
      device.getAddress());

    m = hxm.getClass().getMethod("createRfcommSocket",
      new Class[] { int.class });
    return (BluetoothSocket) m.invoke(hxm, Integer.valueOf(1));
   case REFLECTION_INSECURE:
    hxm = BluetoothAdapter.getDefaultAdapter().getRemoteDevice(
      device.getAddress());
    m = hxm.getClass().getMethod("createInsecureRfcommSocket",
      new Class[] { int.class });
    return (BluetoothSocket) m.invoke(hxm, Integer.valueOf(1));
   }
  } catch (Exception e) {
   Log.e(BT_TAG, "Could not create Insecure RFComm Connection", e);
  }
  return device.createRfcommSocketToServiceRecord(REMOTE_UUID);
 }

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