/**
  * Performs actions based on the selected mode. Browse by source directory or browse by source
  * file
  */
 private void performActions() {
   if (dirRadio.isSelected()) {
     browseBySourceDir();
     MainWindow.setSelectionMode(MainWindow.selection_mode_by_dir);
   } else {
     browseBySourceFile();
     MainWindow.setSelectionMode(MainWindow.selection_mode_by_file);
   }
 }