How to use IKeyboardInputSink to tab between MFC container and WPF User Control

I have a PropertySheet control in MFC dialog which has few tab pages. Inside the tab pages I want to add user control developed in WPF as tab page content. This requirement I have already achieved. However, now final thing which I am left with is setting the tab order properly between between PropertySheet and WPF User control i.e. From Tab page header -> WPF User Control (will move inside the User control as per set tab order) -> OK Button -> Cancel Button -> Apply Button -> Help Button and back to Tab page header. As of now Tabbing only works within the PropertySheet.

I understand in order to move the cursor seamlessly between MFC and WPF controls, I need 开发者_StackOverflow中文版to implement the IKeyboardInputSink interface. But I couldn't find/understand how I should implement this interface. Can someone pls provide info on how I can achieve this?