BookTitlePreference(Context context, ZLResource rootResource, String resourceKey, Book book) {
   super(context, rootResource, resourceKey);
   myBook = book;
   super.setValue(book.getTitle());
 }
 @Override
 protected void setValue(String value) {
   super.setValue(value);
   myBook.setTitle(value);
 }
 @Override
 protected void onDialogClosed(boolean result) {
   super.onDialogClosed(result);
   myOption.setValue(getValue());
 }