How can I rotate only a specific part of screen?

As a question title, I wonder how to rotate only a specific part of screen
For example, most of camera application lock the rotation of screen and only button rotate when device tilts.
How can I implement this? I've already looked xam.plugin.Devicemotion but I don't know how to use it and no example I can find Image may be NSFW.
Clik here to view.
Please help me..Thank you