[android-studio] Android Studio - Auto complete and other features not working

I installed android studio.. it was working fine. Now all the sudden, none of the auto complete features are working.. I can type anything anywhere no variable checking, no help with functions or checking anything. I can still compile the project and I get errors when that happens.

Can anyone please help me out with this issue.

This question is related to android-studio

The answer is

Go File > Invalidate Caches / Restart... > Click at Invalidate and Restart

This really works for me. source: https://code.google.com/p/android/issues/detail?id=61844#c4

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