title: Subclassing a UserControl
body: <p>I am trying to subclass a UserControl after reading the following:
  <a href="https://stackoverflow.com/questions/887519/how-can-a-wpf-usercontrol-inherit-a-wpf-usercontrol">How can a WPF UserControl inherit a WPF UserControl?</a></p>
  
  <p>But I seem to have missed something.</p>
  
  <p>Base class, which is not partial nor does it have an XAML:</p>
  
  <pre><code>namespace HTTPFreeForm
  {
      public class HTTPBaseForm : UserControl, IForm
      /* ... more content ... */
  }
  </code></pre>
  
  <p>Subclass codebehind:</p>
  
  <pre><code>namespace HTTPFreeForm
  {
      public partial class HTTPFreeForm : HTTPBaseForm
      /* ... more content ... */
  }
  </code></pre>
  
  <p>Subclass XAML:</p>
  
  <pre><code>&lt;local:HTTPBaseForm x:Class="HTTPFreeForm.HTTPFreeForm" 
               xmlns:local="clr-namespace:HTTPFreeForm"
               xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
               xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
               xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
               xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
               mc:Ignorable="d" 
               d:DesignHeight="300" d:DesignWidth="300"&gt;
      &lt;!-- ... more content ... --&gt;
  &lt;/local:HTTPBaseForm&gt;
  </code></pre>
  
  <p>When I try to build, I receive the following error:</p>
  
  <blockquote>
    <p>Error 2   The type name 'HTTPBaseForm' does not exist in the type 'HTTPFreeForm.HTTPFreeForm' c:\MyProject\HTTPFreeForm\obj\Debug\HTTPFreeForm.g.cs   42  54  HTTPFreeForm</p>
  </blockquote>
  
  <p><strong>What am I missing or doing wrong?</strong></p>