Android Studio inline compiler showing red errors, but compilation with gradle works fine

When your Android Studio files shows Red . Such  R. file 

The following steps helps

1. Close your project, and in your project folder delete project/.idea
2. Delete ~/.gradle folder.
3. invalidate and restart

Open the project again. Everything should be solved


OR

1) Click on the gradle icon (right side on the android studio)

2) Click on the refresh button and wait for the issue to be resolved :D

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