title: Partial declarations of 'Triangle.MainWindow' must not specify different base classes
body: <p>I've been facing an error that tells me that the partial declarations must not specify a different base class.</p>
  
  <pre><code>public partial class MainWindow : Shape
      {
          public MainWindow()
          {
              InitializeComponent();
              this.Stretch = System.Windows.Media.Stretch.Fill;
              this.StrokeLineJoin = PenLineJoin.Round;
          }
  </code></pre>
  
  <p>I get error from :</p>
  
  <pre><code>public partial class MainWindow : Shape
  </code></pre>
  
  <p>The 'MainWindow' gives me error about the specifying of a different base. How do i go about rectifying this error? </p>
  
  <p>My XAML currently, is the default one:</p>
  
  <pre><code>   &lt;Window x:Class="Triangle.MainWindow"
          xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
          xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
          Title="MainWindow" Height="350" Width="525"&gt;
      &lt;Grid&gt;
  
      &lt;/Grid&gt;
  &lt;/Window&gt;
  </code></pre>
  
  <p>I have yet to edot anything from the XAML as this codes are codes i found somewhere from online and is using it to try out whether or not it work. </p>