title: Can't access R class elements
body: <p>When cleaning out my Workspace folder for a clearer view in Eclipse, I deleted <code>android-support-v7-appcompat</code> project thinking it was a sample code I downloaded a while ago. I figured out it wasn't a wise move and restored it back, importing it from Eclipse. I now have a problem accessing the <code>R</code> elements, even in new automatically generated projects. For example accessing the following elements gives a <code>cannot be resolved or is not a field</code> error on the last element:
  <code>R.layout.activity_crime</code>, <code>R.menu.crime</code>, <code>R.id.action_settings</code>. I tried to rebuild the project, deleting the <code>gen</code> folder so <code>R.java</code> would regenerate but nothing changes. Why is this happening and how can I fix it?</p>