title: Android Rendering Problems Couldn't resolve resource @string/app_name
body: <p>I'm new to android programming and I don't understand what I'm doing wrong.
  I try to make a button like this in the xml file:</p>
  
  <pre><code>&lt;Button
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:text="@string/btnText"
      android:id="@+id/button"
      android:layout_centerVertical="true"
      android:layout_centerHorizontal="true" /&gt;
  </code></pre>
  
  <p>This works fine, without the android:text="@string/btnText" part...</p>
  
  <p>My strings.xml file looks like this:</p>
  
  <pre><code>&lt;string name="btnText"&gt;GO!&lt;/string&gt;
  </code></pre>
  
  <p>I get this error message:
  Rendering Problems Couldn't resolve resource @string/app_name (2 similar errors not shown)</p>
  
  <p>The problem is that the button text says @string/btnText instead of GO!</p>