Android Studio suddenly cannot resolve symbols

Question

Android Studio 0.4.2 was working fine and today I opened it and almost everything was red and the auto-completion had stopped working. I look at the imports and AS seems to

Answer 1

I had the same problem, none of the solutions listed here worked. The problem was my source files where not inside the right folder.

The directory structure MUST be :

[project]\[module]\src\main\java\[yourpackage]\[yourclass.java]