R cannot be resolved to a variable

Question

I would like to fix this error

R cannot be resolved to a variable

I looked up many answers, but I could not get the right one;

Answer 1

If R is missing

• Locate your R.java file, it should be in the folder ./gen/
• If it is missing, and "build project" doesnt build it, one of your XML files has errors, fix them or even delete them, then right-click your project and click build project
• R.java file should be generated