Android – unable to get r.anim in my project

I started some Android programming, and I'm trying to do some animation in my activities. But all references use interpolators and files in the RES / anim folder, which I can't find in the project. In addition, when I use r.anim, I receive an error that it doesn't exist

Is there an API available for download?

thank you

resolvent:

You need to import an R file. You should see something similar to the following in the import list of class files

import <your.app.package>.R