Question TreeView and Tab navigation, make it non focusable?

I have a tree view with controls such as drop down, int field, etc, in a window that has a search field.

The tree view is focusable but this is completely useless:

• you can't even navigate rows with arrow keys
• the tree view shows no borders indicating it has focus

So basically, I'd like to make the tree view as not focusable so when I press Tab it is skipped and next control is focused instead.

Any ideas or suggestions?