QtCreator have two separate file views:

• Project View - shows only project files (included in CMake targets)
• File System View - shows everything

In my experience using both views makes no sense, it produces too much visual noise and takes too much of screen space. So I use File System view only.

However it is sometimes easy to forget adding some source to add_executable(..). It would be very nice If QtCreator could highlight files included in CMakeLists in File System view.