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.
Just make sure you pass context.getApplicationContext() or call getApplicationContext() on any context that is passed in via methods/constructor to your singleton if you decide to store it in any member field. idiot proof example (even if someone would pass in an activity it will grab the app context and use that to instantiate the singleton): … Read more
I had the same issue, but I have resolved it the next: 1) Install jdk1.8… 2) In AndroidStudio File->Project Structure->SDK Location, select your directory where the JDK is located, by default Studio uses embedded JDK but for some reason it produces error=216. 3) Click Ok.