/** Change root path to the given directory. */
  private void changeToDir(String directory) {
    String parent = current != null ? current.getPath() : ".";
    String path = new File(parent, directory).getPath();
    txtCurrentPath.setText(path);

    if (rsc.isServiceBound()) {
      rsc.getService().requestFileList(path);
    }
  }
 /** @see android.support.v4.app.Fragment#onStart() */
 @Override
 public void onStart() {
   super.onStart();
   rsc.bind(getActivity());
 }
 /** @see android.support.v4.app.Fragment#onStop() */
 @Override
 public void onStop() {
   super.onStop();
   rsc.unbind(getActivity());
 }