title: can't get R.anim in my project
body: <p>I started some android programming and I am trying to do some animation in my activity. but all references are using interpolators and files from res/anim folder which I can't find in my project. Also, when I am using R.anim I am getting an error that it doesn't exist. </p>
  
  <p>Is there any API to download?</p>
  
  <p>Thank you</p>