@Override
 public boolean onOptionsItemSelected(MenuItem item) {
   if (item.getItemId() == MenuHelper.MENU_SHARE_ID) {
     BookShareHelper.share(this, book);
     return true;
   }
   return MenuHelper.onOptionsItemSelected(this, item);
 }
 @Override
 public boolean onSearchRequested() {
   return MenuHelper.onSearchRequested(this);
 }
 @Override
 public boolean onCreateOptionsMenu(Menu menu) {
   return MenuHelper.onCreateOptionsMenu(menu, true);
 }