public void onSwapSourceClicked(Boolean onDevice) {
   if (onDevice) {
     mListView.setVisibility(View.GONE);
     mExpandableListView.setVisibility(View.VISIBLE);
     mMainActivity.findViewById(R.id.file_browsing_back).setVisibility(View.GONE);
   } else {
     mExpandableListView.setVisibility(View.GONE);
     mListView.setVisibility(View.VISIBLE);
     mMainActivity.findViewById(R.id.file_browsing_back).setVisibility(View.VISIBLE);
   }
 }