title: How to add images in res folder in android
body: <p>I am trying to add some images to res folder in my android 4.2.2 application. The problem is the project runs fine until whenever I do add, upon running it gives an error </p>
  
  <pre><code>R cannot be resolved to a variable
  </code></pre>
  
  <p>in the <code>src/MainActiviy.java</code> and the <code>R.java</code> file deletes it self from the <code>gen</code> folder.</p>
  
  <p>Now I'm naming the folder <code>drawable-mdp</code> and every <code>png</code> image is also lower cased. But it doesn't seem to bother.
  Thanks!</p>