code: private DialogInterface.OnClickListener createRestoreDefaultsListener() {
          return new DialogInterface.OnClickListener() {
  
              @Override
              public void onClick(final DialogInterface dialog, final int which) {
                  restoreDefaults();
              }
  
          };
      }
docs: Creates and returns a listener, which allows to restore the default values of the fragment's
  preferences.
  
  @return The listener, which has been created, as an instance of the type {@link
  DialogInterface.OnClickListener}