How to get the bluetooth devices as a list?

You should change your code as below:

BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
Set<BluetoothDevice> pairedDevices = mBluetoothAdapter.getBondedDevices();

List<String> s = new ArrayList<String>();
for(BluetoothDevice bt : pairedDevices)
   s.add(bt.getName());

setListAdapter(new ArrayAdapter<String>(this, R.layout.list, s));