TreeItem[] treeItems=viewer.getTree().getItems();
viewer.getControl().setRedraw(false);
Object[] expandedElements=viewer.getExpandedElements();
//force all the elements to be scanned in
viewer.expandAll();
viewer.setExpandedElements(expandedElements);
viewer.getControl().setRedraw(true);
for(TreeItem item: treeItems){
TreeItem target=findTreeItem(item, element);