public static <T extends IItem & IExpandable>void selectAllSubItems(final FastAdapter adapter,T header,boolean select){
  selectAllSubItems(adapter,header,select,false);
}

public static < T extends IItem & IExpandable > void selectAllSubItems ( final FastAdapter adapter , T header , boolean select ) { selectAllSubItems ( adapter , header , select , false ) ; }
select or unselect all sub itmes underneath an expandable item
