title: WPF DataTrigger / DataBinding failing?
body: <p><strong>EDIT: So, it turns out that it was a problem with the code in the VM (embarrassingly enough checking on a property that always returned true [after a refactoring session] ) - I'd kind of assumed that I'd buggered up the databinding as that's the usual suspect (for me at least)
  <br/>Thank you for all the help, and apologies for wasting your time.</strong></p>
  
  <p>Hi, I'm trying to get this to simply change text colour to either Red or Green depending on a boolean Dependency Property in the viewmodel. The triggers are where the problem is... I think?</p>
  
  <pre><code> &lt;TextBlock&gt;
      &lt;TextBlock.Style&gt;
          &lt;Style&gt;
              &lt;Style.Triggers&gt;
                  &lt;DataTrigger Binding="{Binding IsNegativeChange}" Value="true"&gt;
                       &lt;Setter Property="TextBlock.Foreground" Value="Red" /&gt;
                   &lt;/DataTrigger&gt;
  
                   &lt;DataTrigger Binding="{Binding IsNegativeChange}" Value="false"&gt;
                        &lt;Setter Property="TextBlock.Foreground" Value="Green" /&gt;
                    &lt;/DataTrigger&gt;
               &lt;/Style.Triggers&gt;
           &lt;/Style&gt;
       &lt;/TextBlock.Style&gt;
  
      &lt;TextBlock.Text&gt;
           &lt;MultiBinding StringFormat="{}{0} ({1})"&gt;
              &lt;Binding Path="ReturnedData.Change" /&gt;
              &lt;Binding Path="ReturnedData.ChangePercentage" /&gt;
            &lt;/MultiBinding&gt;
      &lt;/TextBlock.Text&gt;
   &lt;/TextBlock&gt;
  </code></pre>
  
  <p>The IsNegativeChange is a member of the ViewModel object itself and so it doesn't need the 'ReturnedData' qualification.</p>
  
  <p>As it stands, the text always appears as green. The ViewModel is correctly returning true/false depending on input..  Help! Is there something stupid I'm missing?</p>
  
  <p>[edited for formatting]</p>
  
  <p>Edit, in the debug window it says:</p>
  
  <p>BindingExpression:Path=IsNegativeChange; DataItem=null; target element is 'TextBlock' (Name=''); <strong>target property is 'NoTarget'</strong> (type 'Object')</p>
  
  <p>Isn't the target set by the  ??</p>