You're going to have to be more detailed with your question if you want a more detailed response. For example, what are you trying to do exactly? Are you running into issues? Or is this more of a question just about how people have used it in the past?
Okay i would like to use AttachmentEditor.Theme.xaml on my application. But i don't know how to use it. may be if you have some tutorials. i am also francophone and i try to express my self.:)