It would be nice and helpful if B4A inspects for external changed files if it get back focus.
In this case external tools like my B4Aconditioner (http://www.b4x.com/android/forum/threads/conditional-compiling-for-b4a.33292/) can manipulate the files and if B4A becomes focus back it detects the file change and ask for reload (Dialog with "yes", "yes for all", "no", "no for all" for example).