title: How to hide the title bar for an Activity in XML with existing custom theme
body: <p>I want to hide the titlebar for some of my activities. The problem is that I applied a style to all my activities, therefore I can't simply set the theme to <code>@android:style/Theme.NoTitleBar</code>. </p>
  
  <p>Using the <strong>NoTitleBar</strong> theme as a parent for my style would remove the title bar from all of my activities.</p>
  
  <p>Can I set a no title style item somewhere?</p>