public void selectInVector(Vector<String> vec) {
   for (ListItem<T> item : items) {
     if (vec.contains(item.dataItem)) {
       item.selected = true;
     } else item.selected = false;
   }
 }
 /** Deselects all items in the list */
 public void selectNone() {
   for (ListItem<T> item : items) {
     item.selected = false;
   }
 }
 /** Selects all items in the list */
 public void selectAll() {
   for (ListItem<T> item : items) {
     item.selected = true;
   }
 }