rem: void setButtonsEnabled( QListBoxItem * ) { setButtonsEnabled(); };
add: void SelectFieldsWidget::setButtonsEnabled() { bool b = false;  for(uint i = 0; i < lbUnSelected->count(); ++i) if ( lbUnSelected->item( i )->isSelected() ) { b = true; break; } pbAdd->setEnabled( b );  int j = lbSelected->currentItem(); b = ( j > -1 && lbSelected->isSelected( j ) );  pbUp->setEnabled( ( j > 0 && b ) );  pbDown->setEnabled( ( j > -1 && j < (int)lbSelected->count()-1 && b ) );   b = false; for(uint i = 0; i < lbSelected->count(); ++i) if ( lbSelected->item( i )->isSelected() ) { b = true; break; } pbRemove->setEnabled( b ); }
context:     void setButtonsEnabled( QListBoxItem * ) { setButtonsEnabled(); };