title: cannot resolve android symbol - android app - intelliJ
body: <p>I am using intellij-idea to develop android app. I created a project with an android module, but none of these : </p>
  
  <pre><code>import android.app.Activity;
  import android.os.Bundle;
  </code></pre>
  
  <p>are recognized, I get <code>cannot resolve android symbol</code>. I googled this issue but none of the remarks I found there seems to debugg my problem</p>