title: Border Color animation in WPF not working in "real-time"
body: <p>In WPF app I am trying to animate a border colour change on MouseEnter event of a TextBox.<br>
  I searched for a while and followed different tutorials, but everything seems to end up the same way:</p>
  
  <ul>
  <li>When the mouse enters the colour of the border changes to what I have set in the animation "From"</li>
  <li>Then nothing happens, no animation at all</li>
  <li>When mouse leaves after a period longer then the animation duration the colour changes to what I have set in the animation "To"</li>
  <li>If the mouse leaves before the animation duration, the colour of the border changes to some colour "in between"  </li>
  </ul>
  
  <p>From this I figured that the animation is happening, but it is not showing it as it animates...<br>
  The code is here:</p>
  
  <pre><code>private void txtSpeakMe_MouseEnter(object sender, MouseEventArgs e)
  {
      ColorAnimation ca = new ColorAnimation();
      ca.From = (Color)ColorConverter.ConvertFromString("#0066FF");
      ca.To = (Color)ColorConverter.ConvertFromString("#FF0000");
      ca.Duration = TimeSpan.FromSeconds(3);
      txtSpeakMe.BorderBrush.BeginAnimation(SolidColorBrush.ColorProperty, ca);
  }
  </code></pre>
  
  <p>Any ideas on why it is not showing the animation as it is happening? I tried animation in XAML using MS tutorials, the same effect - it animates but it is not showing the process of animation until mouse leaves...</p>