Cannot empty a listbox. PLEASE HELP!

Question

Thanks for reading my post.
I have been struggling the whole day to solve a problem with listbox. But I have to ask for help from you guys. thanks in advance.
Here is the scenario:
I have 3 listboxs on my page. The options of the 3 listboxes are dynamically generated based on users input. There is a button that empties all options in listboxes. There is another button to get all selections from 3 listboxes.
Here is what I tested:
1) input something and generate the options for all 3 listboxes, and do some selections.
2) click "EMPTY" button to clean up all listboxes;
3) click "GET" button to get all selections from them. (THIS IS SUPPOSED TO RETURN NOTHING BECAUSE THEY ARE ALL REMOVED)
Here is the problem:
After "EMPTY" all options in 3 listboxes, "GET" button still return all previous selections. ????
Here is what I did about EMPTY and GET
1) EMPTY: I tried all followings:
- listbox1.setItems(null);
- listbox1.setItems(new Option[0]);
- children = listbox1.getChildren(); children.clear()
- I even tried this: listbox1.setItems(newOptionArray), still get the old selections unless I selected something in the newOptionArray
2) GET: the method that I used is listbox1.getSelected();
Any Idea?

Answer 1

Yes guys, you are right. I got confused by the options and selections.
After reading the replies from both of you and following material http://developers.sun.com/prodtech/javatools/jscreator/reference/themes/jsf/listbox_comps.pdf
I finially realized my mistake.
thanks a lot!