Delphi: Combobox whith ownerdraw and autocomplete

I'm trying to have a combobox working like the "Category" one you can find in MS Money:

Items are :

Item 1
   - Sub item 1
   - Sub item 2
Item 2
   - S开发者_Python百科ub item a
   - Sub item b
   - ...

When you select Sub item 1, it shows: "Item 1 : Sub item 1"

I manage to do that with OwnerDraw style, but then the combobox is in read-only. I want to be able to add custom items.

Does someone know how to do that ? (Or a third party component)

Your question is confusing but I suggest you to explore the opensource Monex project.

It seems to uses some components implementing similar features.