EditorSearchView is focus in FindWhat or ReplaceWith?

Hello,

I need to set the FindWhat and ReplaceWith text strings programmatically. I can do this with the EditorSearchView.SearchOption.FindText and ReplaceText.

The problem I am having is determining which has focus, the FindText or the ReplaceText controls.

When the EditorSearchView.Mode is Replace, how do I determine which edit control if either has focus?

A little extra background info:

I'm hosting the WPF SyntaxEditor in HwndSource inside of a C++ application. The C++ handlers for the edit menu functions, cut, copy, paste, are acting by accessing the SyntaxEditor and the EditorSearchView by way of attached properties. My current difficulty is in implementing the attached property to handle the paste function into the appropriate edit control inside the EditSearchView.

Thanks for your help!

Pete