title: Colors in main_activity.xml are not refreshed after changing them in colors.xml
body: <p>I'm trying to change <code>@color/colorPrimary</code> to any other value but it doesn't change anything in activity_main.xml. Do I also have to change it somewhere else?</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;resources&gt;
     &lt;color name="colorPrimary"&gt;#33b5e5&lt;/color&gt;
     &lt;color name="colorPrimaryDark"&gt;#7A1EA1&lt;/color&gt;
     &lt;color name="colorAccent"&gt;#68EFAD&lt;/color&gt;
     &lt;color name="white"&gt;#ffffff&lt;/color&gt;
     &lt;color name="hintColor"&gt;#999999&lt;/color&gt;
  &lt;/resources&gt;
  </code></pre>