title: Notify binding for static properties in static classes
body: <p>I found a notify property changed example for <strong>static</strong> properties in <strong>static</strong> class. but it doesn't update any changes in TextBlock. Here are the codes.</p>
  
  <p>First binding is working with the "test" string in constructor but StaticPropertyChanged is always null.</p>
  
  <pre><code>public static class InteractionData
  {
      public static List&lt;string&gt; SelectedDirectories { get; set; }
      private static string errorMessage { get; set; }
      public static string ErrorMessgae
      {
          get { return errorMessage; }
          set
          {
              errorMessage = value;
              NotifyStaticPropertyChanged("errorMessage");
          }
      }
  
      static InteractionData()
      {
          SelectedDirectories = new List&lt;string&gt;();
          errorMessage = "test";
      }
  
      public static event EventHandler&lt;PropertyChangedEventArgs&gt; StaticPropertyChanged;
      private static void NotifyStaticPropertyChanged(string propertyName)
      {
          if (StaticPropertyChanged != null)
              StaticPropertyChanged(null, new PropertyChangedEventArgs(propertyName));
      }
  }
  </code></pre>
  
  <p>In View ...</p>
  
  <pre><code>     xmlns:error ="clr-namespace:CopyBackup.Providers"
  &lt;TextBlock Text="{Binding Source={x:Static error:InteractionData.ErrorMessgae} ,Mode=OneWay,  UpdateSourceTrigger=PropertyChanged}"/&gt;
  </code></pre>
  
  <p>Wherever I change the property, TextBlock doesn't update. </p>
  
  <p>Appreciate</p>