Tab Navigation RadGridView

[Devid]

I have a Grid and inside that grid I have a RadGridView filled with items. Below the RadGridView I have four buttons.

What I want is that by pressing the Tab key I navigate like this: When I open the windows and Press Tab I focus on the first item in the view of the RadGridView, on the second Tab press I jump out of the RadGridView and the focus is now on the Button below. On the next Tab press I jump to the next button and so on and so on till I reach the end and than I start the same from the beginning.

In the RadGridView if I want to move through the Items I do so with the Arrow keys Up and Down.

How can I do that ? I set in the RadGridView IsTabStop="False" but that is not enough, because on the first Tab press I want to Focus on the first item in the View of the RadGridView and then on the second Tab press I want to jump out to the next button. 

[Devid]

Any help ?

What I want to do is actually exactly how Tab Navigation works in Windows File Explorer. With Tab you just focus on the first item on the Grid, on the second Tab you move to the next element.