title: WPF animation based on property change triggers at start
body: <p>I'm trying to animate a Border's color when a value that is bound to a textbox's Text property changes: </p>
  
  <pre><code>&lt;Border x:Name="border" BorderThickness="3" BorderBrush="Blue" HorizontalAlignment="Center" VerticalAlignment="Center"&gt;
      &lt;TextBlock Background="White" TextAlignment="Center" FontSize="24" 
                         Text="{Binding Value, NotifyOnTargetUpdated=True}"&gt;
          &lt;TextBlock.Triggers&gt;
              &lt;EventTrigger RoutedEvent="Binding.TargetUpdated"&gt;
                  &lt;EventTrigger.Actions&gt;
                      &lt;BeginStoryboard&gt;
                          &lt;Storyboard&gt;
                              &lt;ColorAnimation To="Yellow"
                                  Storyboard.TargetName="border"
                                  AutoReverse="True"
                                  Storyboard.TargetProperty="(Border.BorderBrush).(SolidColorBrush.Color)"
                                  FillBehavior="Stop"
                                  Duration="0:0:0.5"
                                  RepeatBehavior="5x" /&gt;
                          &lt;/Storyboard&gt;
                      &lt;/BeginStoryboard&gt;
                  &lt;/EventTrigger.Actions&gt;
              &lt;/EventTrigger&gt;
          &lt;/TextBlock.Triggers&gt;
      &lt;/TextBlock&gt;
  &lt;/Border&gt;
  </code></pre>
  
  <p>The problem is that the animation is triggered even when the application launches and the value has not been set once yet.
  Is there a solution to avoid this?</p>