enable Annotation Processors option in Android Studio 2.2
Close the project. In the "Welcome to Android Studio" dialog click "Configure" in the bottom right corner.
Then,
Settings > Build, Execution, Deployment > Compiler > Annotation Processors. Tick 'Enable annotation processing'.
If that does not work. Delete the project from "Welcome to Android Studio" dialog and open from new.
Worked for me.
- Close all your AndroidStudio Project
See
Click Configure-->Setting See
You can enable Annotation Processors without closing your project in Android Studio 2.3:
File -> Other Settings -> Default Settings
Build, Execution, Deployment -> Compiler -> Annotation Processors -> Enable annotation processing.
Don't forget to clean, build, invalidate and restart after that.
Cheers!