Which version of CM are you using? I experienced the same problem as you a while ago and wrote a short item about it, see here.
Today, I tested a new project using the latest CM source code, and it seems to partially work without code-behind files? I have a
Today, I tested a new project using the latest CM source code, and it seems to partially work without code-behind files? I have a
Page view that seem to work without the corresponding code-behind file, but a UserControl settings view does not seem to work without the code-behind.