// find deleted elements
Set<Collapsible> collapsibleSet = m_CollapsibleElements.keySet();
Iterator<Collapsible> it = collapsibleSet.iterator();
ArrayList<Collapsible> deletedItems = new ArrayList<Collapsible>();
while (it.hasNext()) {
Collapsible collapsible = it.next();
ProjectionAnnotation annotation = m_CollapsibleElements.get(collapsible);
// if the element does not exist in the new list, remove it
boolean bFound=false;
for(int i=0;i<newCollapsibles.length;i++){
if (newCollapsibles[i].equals(collapsible)){