combo box vs list box dealing with textbox

Here i would like to have a combo box or list box that have a list of subject and when i push on one of them on the other comnbo or list box it will show a diffrent list ther and when i push on one the items on the second list i would have a specific descrption on a rext box below.Iam having problem trying make the items change when i push on one of them . Exemple i could have a combo box having in it : cars , boat , houses and the other combo box would show different content depending if i push the cars or boat. And then if i push for exemple cars well on the other combo box i would have a cars list and if i push on as exemple honda prelude ther i would have a wanted descrption of that in the text box below. I hope i have been clear enough ther hehe. thanks in advance !!!

How about some code?, so that people trying to answer your question, have some base to start with!.

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Idea should be
1. If you dont want people to entering any data, but just select from a set, then have the combo boxes of style 2 - Drop Down List only
2. In the _Click event, of the top level combo, clear the contents of the (i) 2nd level combo, (2) the list box (3) the text box.
Fill the 2nd level combo with details as per selection in COmbo1
3. When Combo 2 is selected, (i) Clear the contents of the List box (2) and the text box, and then (3) fill the list box with details relating to selection as per combo1 & COmbo2
Catch the _Click event of Combo2.

4. When user clicks on the Listbox, then
(i) clear the contents of the text box only and (ii) add the new contents as per selection in List box.
Catch the _Click event in the Listbox.

This technique will make sure that inconsistencies are removed.

And lastly, your data validation routine should take care of the "empty data" in any of the controls. ie. No selection is done is Combo 2 or Listbox or Textbox contents are empty etc..


RK